1660 lines
69 KiB
Plaintext
1660 lines
69 KiB
Plaintext
README
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======
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This README file discusses the port of NuttX to the Atmel SAM E70 Xplained
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Evaluation Kit (ATSAME70-XPLD). This board features the ATSAME70Q21 Cortex-M7
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microcontroller.
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Contents
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========
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- Status/Open Issues
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- Serial Console
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- SD card
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- Automounter
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- LEDs and Buttons
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- AT24MAC402 Serial EEPROM
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- Program FLASH Access
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- Networking
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- USBHS Device Controller Driver
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- MCAN1 Loopback Test
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- SPI Slave
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- Click Shield
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- Tickless OS
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- Debugging
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- Using OpenOCD and GDB to flash via the EDBG chip
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- Configurations
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Status/Open Issues
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==================
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2015-11-30: The basic NSH configuration is function with serial console
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via the EDBG VCOM and LED and buttons support. SDRAM and the HSMCI
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SD card slot also appear to be fully functional.
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See also configs/samv71-xult/README.txt
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Serial Console
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==============
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The SAME70-XPLD has no on-board RS-232 drivers so it will be necessary to
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use either the VCOM or an external RS-232 driver. Here are some options.
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- Arduino Serial Shield: One option is to use an Arduino-compatible
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serial shield. This will use the RXD and TXD signals available at pins
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0 an 1, respectively, of the Arduino "Digital Low" connector. On the
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SAME70-XPLD board, this corresponds to UART3:
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------ ------ ------- ------- --------
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Pin on SAME70 Arduino Arduino SAME70
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J503 PIO Name Pin Function
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------ ------ ------- ------- --------
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1 PD28 D0/RX0 0 URXD3
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2 PD30 D1/TX0 1 UTXD3
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------ ------ ------- ------- --------
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In this configuration, an external RS232 driver can also be used
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instead of the shield. Simply connext as follows:
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--------- -----------
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Arduino RS-232
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Pin Label Connection
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--------- -----------
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D0 (RXD) RX
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D1 (TXD) TX
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GND GND
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5VO Vcc
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--------- -----------
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- Arduino Communications. Additional UART/USART connections are available
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on the Arduino Communications connection J505 and J507:
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--------- ---------- --------------------------------
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Connector SAME70 Pin Description
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--------- ---------- --------------------------------
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J503 1 URXD3 PD28 Standard Arduino serial (D0/RXD)
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J503 2 UTXD3 PD30 Standard Arduino serial (D1/TXD)
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--------- ---------- --------------------------------
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J505 3 URXD4 PD18 Arduino D19
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J505 4 UTXD4 PD19 Arduino D18
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J505 5 RXD2 PD15 Arduino D17
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J505 6 TXD2 PD16 Arduino D16
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J505 7 RXD0 PB0 Arduino D15
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J505 8 TXD0 PB1 Arduino D14
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--------- ---------- --------------------------------
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J507 27 RXD1 PA21 Arduino D46
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J507 28 TXD1 PB4 Arduino D47
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--------- ---------- --------------------------------
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- SAMV7-XULT EXTn connectors. USART pins are also available the EXTn
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connectors. The following are labelled in the User Guide for USART
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functionality:
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SAME70 Xplained Connectors
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--------- ---------- --------------------------------
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Connector SAME70 Pin Description
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--------- ---------- --------------------------------
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J401 13 RXD0 PB0 EXT1 UART_RX
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J401 14 TXD0 PB1 EXT1 UART_7X
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--------- ---------- --------------------------------
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J402 13 RXD1 PA21 EXT2 UART_RX
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J402 14 TXD1 PB4 EXT2 UART_TX
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--------- ---------- --------------------------------
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- VCOM. The Virtual Com Port gateway is available on USART1:
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EDBG VCOM Interface
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---------------- --------- --------------------------
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EDBG Singal SAME70
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---------------- --------- --------------------------
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EDBG_CDC_UART_RX TXD1 PB4
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EDBG_CDC_UART_TX RXD1 PA21
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---------------- --------- --------------------------
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Any of these options can be selected as the serial console by:
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1. Enabling the UART/USART peripheral in the
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"System Type -> Peripheral Selection" menu, then
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2. Configuring the peripheral in the "Drivers -> Serial Configuration"
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menu.
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NOTE: If USART1 is used (TXD1, RXD1), then PB4 must be reconfigured in the
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SUPC. Normally, PB4 is TDI. When it is reconfigured for use with USART1,
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the capability to debug is lost! If you plan to debug you should most
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certainly not use USART1.
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SD Card
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=======
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Card Slot
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---------
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The SAM E70 Xplained has one standard SD card connector that is connected to
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the High Speed Multimedia Card Interface (HSMCI) of the SAM
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E70. SD card connector:
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------ ----------------- ---------------------
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SAME70 SAME70 Shared functionality
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Pin Function
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------ ----------------- ---------------------
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PA30 MCDA0 (DAT0)
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PA31 MCDA1 (DAT1)
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PA26 MCDA2 (DAT2)
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PA27 MCDA3 (DAT3)
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PA25 MCCK (CLK) Shield
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PA28 MCCDA (CMD)
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PC16 Card Detect (C/D) Shield
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------ ----------------- ---------------------
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Configuration Settings
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----------------------
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Enabling HSMCI support. The SAMV7-XULT provides a one, full-size SD memory
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card slots. The full size SD card slot connects via HSMCI0. Support for
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the SD slots can be enabled with the following settings:
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System Type->SAMV7 Peripheral Selection
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CONFIG_SAMV7_HSMCI0=y : To enable HSMCI0 support
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CONFIG_SAMV7_XDMAC=y : XDMAC is needed by HSMCI0/1
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System Type
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CONFIG_SAMV7_GPIO_IRQ=y : PIO interrupts needed
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CONFIG_SAMV7_GPIOD_IRQ=y : Card detect pin is on PD18
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Device Drivers -> MMC/SD Driver Support
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CONFIG_MMCSD=y : Enable MMC/SD support
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CONFIG_MMSCD_NSLOTS=1 : One slot per driver instance
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CONFIG_MMCSD_MULTIBLOCK_DISABLE=y : (REVISIT)
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CONFIG_MMCSD_HAVE_CARDDETECT=y : Supports card-detect PIOs
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CONFIG_MMCSD_MMCSUPPORT=n : Interferes with some SD cards
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CONFIG_MMCSD_SPI=n : No SPI-based MMC/SD support
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CONFIG_MMCSD_SDIO=y : SDIO-based MMC/SD support
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CONFIG_SDIO_DMA=y : Use SDIO DMA
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CONFIG_SDIO_BLOCKSETUP=y : Needs to know block sizes
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RTOS Features -> Work Queue Support
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CONFIG_SCHED_WORKQUEUE=y : Driver needs work queue support
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Application Configuration -> NSH Library
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CONFIG_NSH_ARCHINIT=y : NSH board-initialization, OR
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CONFIG_BOARD_INITIALIZE=y
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Using the SD card
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-----------------
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1) After booting, the HSCMI device will appear as /dev/mmcsd0.
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2) If you try mounting an SD card with nothing in the slot, the mount will
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fail:
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nsh> mount -t vfat /dev/mmcsd0 /mnt/sd0
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nsh: mount: mount failed: 19
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NSH can be configured to provide errors as strings instead of
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numbers. But in this case, only the error number is reported. The
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error numbers can be found in nuttx/include/errno.h:
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#define ENODEV 19
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#define ENODEV_STR "No such device"
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So the mount command is saying that there is no device or, more
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correctly, that there is no card in the SD card slot.
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3) Inserted the SD card. Then the mount should succeed.
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nsh> mount -t vfat /dev/mmcsd0 /mnt/sd0
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nsh> ls /mnt/sd1
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/mnt/sd1:
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atest.txt
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nsh> cat /mnt/sd1/atest.txt
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This is a test
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NOTE: See the next section entitled "Auto-Mounter" for another way
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to mount your SD card.
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4) Before removing the card, you must umount the file system. This is
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equivalent to "ejecting" or "safely removing" the card on Windows: It
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flushes any cached data to an SD card and makes the SD card unavailable
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to the applications.
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nsh> umount -t /mnt/sd0
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It is now safe to remove the card. NuttX provides into callbacks
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that can be used by an application to automatically unmount the
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volume when it is removed. But those callbacks are not used in
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these configurations.
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Auto-Mounter
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============
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NuttX implements an auto-mounter than can make working with SD cards
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easier. With the auto-mounter, the file system will be automatically
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mounted when the SD card is inserted into the HSMCI slot and automatically
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unmounted when the SD card is removed.
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Here is a sample configuration for the auto-mounter:
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File System Configuration
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CONFIG_FS_AUTOMOUNTER=y
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Board-Specific Options
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CONFIG_SAME70XPLAINED_HSMCI0_AUTOMOUNT=y
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CONFIG_SAME70XPLAINED_HSMCI0_AUTOMOUNT_FSTYPE="vfat"
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CONFIG_SAME70XPLAINED_HSMCI0_AUTOMOUNT_BLKDEV="/dev/mmcsd0"
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CONFIG_SAME70XPLAINED_HSMCI0_AUTOMOUNT_MOUNTPOINT="/mnt/sdcard"
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CONFIG_SAME70XPLAINED_HSMCI0_AUTOMOUNT_DDELAY=1000
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CONFIG_SAME70XPLAINED_HSMCI0_AUTOMOUNT_UDELAY=2000
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WARNING: SD cards should never be removed without first unmounting
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them. This is to avoid data and possible corruption of the file
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system. Certainly this is the case if you are writing to the SD card
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at the time of the removal. If you use the SD card for read-only access,
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however, then I cannot think of any reason why removing the card without
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mounting would be harmful.
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LEDs and Buttons
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================
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LEDs
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----
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A single LED is available driven by PC8.
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This LED is not used by the board port unless CONFIG_ARCH_LEDS is
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defined. In that case, the usage by the board port is defined in
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include/board.h and src/sam_autoleds.c. The LED is used to encode
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OS-related events as follows:
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------------------- ----------------------- ------
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SYMBOL Meaning LED
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------------------- ----------------------- ------
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LED_STARTED NuttX has been started OFF
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LED_HEAPALLOCATE Heap has been allocated OFF
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LED_IRQSENABLED Interrupts enabled OFF
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LED_STACKCREATED Idle stack created ON
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LED_INIRQ In an interrupt N/C
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LED_SIGNAL In a signal handler N/C
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LED_ASSERTION An assertion failed N/C
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LED_PANIC The system has crashed FLASH
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Thus if the LED is statically on, NuttX has successfully booted and is,
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apparently, running normally. If the LED is flashing at approximately
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2Hz, then a fatal error has been detected and the system has halted.
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Buttons
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-------
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SAM E70 Xplained contains two mechanical buttons. One button is the RESET
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button connected to the SAM E70 reset line and the other, PA11, is a generic
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user configurable button. When a button is pressed it will drive the I/O
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line to GND.
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NOTE: There are no pull-up resistors connected to the generic user buttons
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so it is necessary to enable the internal pull-up in the SAM E70 to use the
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button.
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AT24MAC402 Serial EEPROM
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========================
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Ethernet MAC Address
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--------------------
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The SAM E70 Xplained features one external AT24MAC402 serial EEPROM with an
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EIA-48 MAC address connected to the SAM E70 through I2C. This device
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contains a MAC address for use with the Ethernet interface.
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Connectivity:
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------ -------- --------
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SAME70 SAME70 I2C
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Pin Function Function
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------ -------- --------
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PA03 TWID0 SDA
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PA04 TWICK0 SCL
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------ -------- --------
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I2C address:
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The 7-bit addresses of the AT24 part are 0b1010AAA for the normal 2Kbit
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memory and 0b1011aaa for the "extended memory" where aaa is the state of
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the A0, A1, and A3 pins on the part. On the SAME70-XPLD board, these
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are all pulled high so the full, 7-bit address is 0x5f.
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Configuration
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-------------
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System Type -> SAMV7 Peripheral Support
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CONFIG_SAMV7_TWIHS0=y : Used to access the EEPROM
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CONFIG_SAMV7_TWIHS0_FREQUENCY=100000
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Device drivers -> Memory Technology Devices
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CONFIG_MTD_AT24XX=y : Enable the AT24 device driver
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CONFIG_AT24XX_SIZE=2 : Normal EEPROM is 2Kbit (256b)
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CONFIG_AT24XX_ADDR=0x57 : Normal EEPROM address */
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CONFIG_AT24XX_EXTENDED=y : Supports an extended memory region
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CONFIG_AT24XX_EXTSIZE=160 : Extended address up to 0x9f
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MTD Configuration Data
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----------------------
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The AT24 EEPROM can also be used to storage of up to 256 bytes of
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configuration data:
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Device drivers -> Memory Technology Devices
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The configuration data device will appear at /dev/config.
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Networking
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==========
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KSZ8081RNACA Connections
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------------------------
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------ --------- ---------
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SAME70 SAME70 Ethernet
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Pin Function Functio
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------ --------- ---------
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PD0 GTXCK REF_CLK
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PD1 GTXEN TXEN
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PD2 GTX0 TXD0
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PD3 GTX1 TXD1
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PD4 GRXDV CRS_DV
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PD5 GRX0 RXD0
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PD6 GRX1 RXD1
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PD7 GRXER RXER
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PD8 GMDC MDC
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PD9 GMDIO MDIO
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PA14 GPIO INTERRUPT
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PC10 GPIO RESET
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------ --------- ---------
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Selecting the GMAC peripheral
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-----------------------------
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System Type -> SAMV7 Peripheral Support
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CONFIG_SAMV7_EMAC0=y : Enable the GMAC peripheral (aka, EMAC0)
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CONFIG_SAMV7_TWIHS0=y : We will get the MAC address from the AT24 EEPROM
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CONFIG_SAMV7_TWIHS0_FREQUENCY=100000
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System Type -> EMAC device driver options
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CONFIG_SAMV7_EMAC0_NRXBUFFERS=16 : Set aside some RS and TX buffers
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CONFIG_SAMV7_EMAC0_NTXBUFFERS=8
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CONFIG_SAMV7_EMAC0_RMII=y : The RMII interfaces is used on the board
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CONFIG_SAMV7_EMAC0_AUTONEG=y : Use autonegotiation
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CONFIG_SAMV7_EMAC0_PHYADDR=1 : KSZ8061 PHY is at address 1
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CONFIG_SAMV7_EMAC0_PHYSR=30 : Address of PHY status register on KSZ8061
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CONFIG_SAMV7_EMAC0_PHYSR_ALTCONFIG=y : Needed for KSZ8061
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CONFIG_SAMV7_EMAC0_PHYSR_ALTMODE=0x7 : " " " " " "
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CONFIG_SAMV7_EMAC0_PHYSR_10HD=0x1 : " " " " " "
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CONFIG_SAMV7_EMAC0_PHYSR_100HD=0x2 : " " " " " "
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CONFIG_SAMV7_EMAC0_PHYSR_10FD=0x5 : " " " " " "
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CONFIG_SAMV7_EMAC0_PHYSR_100FD=0x6 : " " " " " "
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PHY selection. Later in the configuration steps, you will need to select
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the KSZ8061 PHY for EMAC (See below)
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Networking Support
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CONFIG_NET=y : Enable Neworking
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CONFIG_NET_SOCKOPTS=y : Enable socket operations
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CONFIG_NET_ETH_MTU=562 : Maximum packet size (MTU) 1518 is more standard
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CONFIG_NET_ETH_TCP_RECVWNDO=562 : Should be the same as CONFIG_NET_ETH_MTU
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CONFIG_NET_ARP=y : ARP support should be enabled
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CONFIG_NET_ARP_SEND=y : Use ARP to get peer address before sending
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CONFIG_NET_TCP=y : Enable TCP/IP networking
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CONFIG_NET_TCPBACKLOG=y : Support TCP/IP backlog
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CONFIG_NET_TCP_READAHEAD=y : Enable TCP read-ahead buffering
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CONFIG_NET_TCP_WRITE_BUFFERS=y : Enable TCP write buffering
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CONFIG_NET_UDP=y : Enable UDP networking
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CONFIG_NET_BROADCAST=y : Support UDP broadcase packets
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CONFIG_NET_ICMP=y : Enable ICMP networking
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CONFIG_NET_ICMP_SOCKET=y : Needed for NSH ping command
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: Defaults should be okay for other options
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Device drivers -> Network Device/PHY Support
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CONFIG_NETDEVICES=y : Enabled PHY selection
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CONFIG_ETH0_PHY_KSZ8061=y : Select the KSZ8061 PHY used with EMAC0
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Device drivers -> Memory Technology Devices
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CONFIG_MTD_AT24XX=y : Enable the AT24 device driver
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CONFIG_AT24XX_SIZE=2 : Normal EEPROM is 2Kbit (256b)
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CONFIG_AT24XX_ADDR=0x57 : Normal EEPROM address */
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CONFIG_AT24XX_EXTENDED=y : Supports an extended memory region
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CONFIG_AT24XX_EXTSIZE=160 : Extended address up to 0x9f
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RTOS Features ->Work Queue Support
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CONFIG_SCHED_WORKQUEUE=y : Work queue support is needed
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CONFIG_SCHED_HPWORK=y
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CONFIG_SCHED_HPWORKSTACKSIZE=2048 : Might need to be increased
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Application Configuration -> Network Utilities
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CONFIG_NETDB_DNSCLIENT=y : Enable host address resolution
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CONFIG_NETUTILS_TELNETD=y : Enable the Telnet daemon
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CONFIG_NETUTILS_TFTPC=y : Enable TFTP data file transfers for get and put commands
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CONFIG_NETUTILS_NETLIB=y : Network library support is needed
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CONFIG_NETUTILS_WEBCLIENT=y : Needed for wget support
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: Defaults should be okay for other options
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Application Configuration -> NSH Library
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CONFIG_NSH_TELNET=y : Enable NSH session via Telnet
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CONFIG_NSH_IPADDR=0x0a000002 : Select an IP address
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CONFIG_NSH_DRIPADDR=0x0a000001 : IP address of gateway/host PC
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CONFIG_NSH_NETMASK=0xffffff00 : Netmask
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CONFIG_NSH_NOMAC=n : We will get the IP address from EEPROM
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: Defaults should be okay for other options
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Cache-Related Issues
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--------------------
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I- and D-Caches can be enabled but the D-Cache must be enabled in write-
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through mode. This is to work around issues with the RX and TX descriptors
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with are 8-bytes in size. But the D-Cache cache line size is 32-bytes.
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That means that you cannot reload, clean or invalidate a descriptor without
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also effecting three neighboring descriptors. Setting write through mode
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eliminates the need for cleaning the D-Cache. If only reloading and
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invalidating are done, then there is no problem.
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Using the network with NSH
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--------------------------
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So what can you do with this networking support? First you see that
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NSH has several new network related commands:
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ifconfig, ifdown, ifup: Commands to help manage your network
|
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get and put: TFTP file transfers
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wget: HTML file transfers
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ping: Check for access to peers on the network
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Telnet console: You can access the NSH remotely via telnet.
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You can also enable other add on features like full FTP or a Web
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Server or XML RPC and others. There are also other features that
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you can enable like DHCP client (or server) or network name
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resolution.
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By default, the IP address of the SAME70-XPLD will be 10.0.0.2 and
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it will assume that your host is the gateway and has the IP address
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10.0.0.1.
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nsh> ifconfig
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eth0 HWaddr 00:e0:de:ad:be:ef at UP
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IPaddr:10.0.0.2 DRaddr:10.0.0.1 Mask:255.255.255.0
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You can use ping to test for connectivity to the host (Careful,
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Window firewalls usually block ping-related ICMP traffic). On the
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target side, you can:
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nsh> ping 10.0.0.1
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PING 10.0.0.1 56 bytes of data
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56 bytes from 10.0.0.1: icmp_seq=1 time=0 ms
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56 bytes from 10.0.0.1: icmp_seq=2 time=0 ms
|
|
56 bytes from 10.0.0.1: icmp_seq=3 time=0 ms
|
|
56 bytes from 10.0.0.1: icmp_seq=4 time=0 ms
|
|
56 bytes from 10.0.0.1: icmp_seq=5 time=0 ms
|
|
56 bytes from 10.0.0.1: icmp_seq=6 time=0 ms
|
|
56 bytes from 10.0.0.1: icmp_seq=7 time=0 ms
|
|
56 bytes from 10.0.0.1: icmp_seq=8 time=0 ms
|
|
56 bytes from 10.0.0.1: icmp_seq=9 time=0 ms
|
|
56 bytes from 10.0.0.1: icmp_seq=10 time=0 ms
|
|
10 packets transmitted, 10 received, 0% packet loss, time 10100 ms
|
|
|
|
NOTE: In this configuration is is normal to have packet loss > 0%
|
|
the first time you ping due to the default handling of the ARP
|
|
table.
|
|
|
|
On the host side, you should also be able to ping the SAME70-XPLD:
|
|
|
|
$ ping 10.0.0.2
|
|
|
|
You can also log into the NSH from the host PC like this:
|
|
|
|
$ telnet 10.0.0.2
|
|
Trying 10.0.0.2...
|
|
Connected to 10.0.0.2.
|
|
Escape character is '^]'.
|
|
sh_telnetmain: Session [3] Started
|
|
|
|
NuttShell (NSH) NuttX-7.9
|
|
nsh> help
|
|
help usage: help [-v] [<cmd>]
|
|
|
|
[ echo ifconfig mkdir mw sleep
|
|
? exec ifdown mkfatfs ping test
|
|
cat exit ifup mkfifo ps umount
|
|
cp free kill mkrd put usleep
|
|
cmp get losetup mh rm wget
|
|
dd help ls mount rmdir xd
|
|
df hexdump mb mv sh
|
|
|
|
Builtin Apps:
|
|
nsh>
|
|
|
|
NOTE: If you enable this feature, you experience a delay on booting.
|
|
That is because the start-up logic waits for the network connection
|
|
to be established before starting NuttX. In a real application, you
|
|
would probably want to do the network bringup on a separate thread
|
|
so that access to the NSH prompt is not delayed.
|
|
|
|
This delay will be especially long if the board is not connected to
|
|
a network. On the order of a minute! You will probably think that
|
|
NuttX has crashed! And then, when it finally does come up, the
|
|
network will not be available.
|
|
|
|
Network Initialization Thread
|
|
-----------------------------
|
|
There is a configuration option enabled by CONFIG_NSH_NETINIT_THREAD
|
|
that will do the NSH network bring-up asynchronously in parallel on
|
|
a separate thread. This eliminates the (visible) networking delay
|
|
altogether. This networking initialization feature by itself has
|
|
some limitations:
|
|
|
|
- If no network is connected, the network bring-up will fail and
|
|
the network initialization thread will simply exit. There are no
|
|
retries and no mechanism to know if the network initialization was
|
|
successful.
|
|
|
|
- Furthermore, there is no support for detecting loss of the network
|
|
connection and recovery of networking when the connection is restored.
|
|
|
|
Both of these shortcomings can be eliminated by enabling the network
|
|
monitor:
|
|
|
|
Network Monitor
|
|
---------------
|
|
By default the network initialization thread will bring-up the network
|
|
then exit, freeing all of the resources that it required. This is a
|
|
good behavior for systems with limited memory.
|
|
|
|
If the CONFIG_NSH_NETINIT_MONITOR option is selected, however, then the
|
|
network initialization thread will persist forever; it will monitor the
|
|
network status. In the event that the network goes down (for example, if
|
|
a cable is removed), then the thread will monitor the link status and
|
|
attempt to bring the network back up. In this case the resources
|
|
required for network initialization are never released.
|
|
|
|
Pre-requisites:
|
|
|
|
- CONFIG_NSH_NETINIT_THREAD as described above.
|
|
|
|
- CONFIG_NETDEV_PHY_IOCTL. Enable PHY IOCTL commands in the Ethernet
|
|
device driver. Special IOCTL commands must be provided by the Ethernet
|
|
driver to support certain PHY operations that will be needed for link
|
|
management. There operations are not complex and are implemented for
|
|
the Atmel SAMV7 family.
|
|
|
|
- CONFIG_ARCH_PHY_INTERRUPT. This is not a user selectable option.
|
|
Rather, it is set when you select a board that supports PHY interrupts.
|
|
In most architectures, the PHY interrupt is not associated with the
|
|
Ethernet driver at all. Rather, the PHY interrupt is provided via some
|
|
board-specific GPIO and the board-specific logic must provide support
|
|
for that GPIO interrupt. To do this, the board logic must do two things:
|
|
(1) It must provide the function arch_phy_irq() as described and
|
|
prototyped in the nuttx/include/nuttx/arch.h, and (2) it must select
|
|
CONFIG_ARCH_PHY_INTERRUPT in the board configuration file to advertise
|
|
that it supports arch_phy_irq(). This logic can be found at
|
|
nuttx/configs/same70-xplained/src/sam_ethernet.c.
|
|
|
|
- And a few other things: UDP support is required (CONFIG_NET_UDP) and
|
|
signals must not be disabled (CONFIG_DISABLE_SIGNALS).
|
|
|
|
Given those prerequisites, the network monitor can be selected with these
|
|
additional settings.
|
|
|
|
Networking Support -> Networking Device Support
|
|
CONFIG_NETDEV_PHY_IOCTL=y : Enable PHY ioctl support
|
|
|
|
Application Configuration -> NSH Library -> Networking Configuration
|
|
CONFIG_NSH_NETINIT_THREAD : Enable the network initialization thread
|
|
CONFIG_NSH_NETINIT_MONITOR=y : Enable the network monitor
|
|
CONFIG_NSH_NETINIT_RETRYMSEC=2000 : Configure the network monitor as you like
|
|
CONFIG_NSH_NETINIT_SIGNO=18
|
|
|
|
USBHS Device Controller Driver
|
|
==============================
|
|
The USBHS device controller driver is enabled with he following configuration
|
|
settings:
|
|
|
|
Device Drivers -> USB Device Driver Support
|
|
CONFIG_USBDEV=y : Enable USB device support
|
|
For full-speed/low-power mode:
|
|
CONFIG_USBDEV_DUALSPEED=n : Disable High speed support
|
|
For high-speed/normal mode:
|
|
CONFIG_USBDEV_DUALSPEED=y : Enable High speed support
|
|
CONFIG_USBDEV_DMA=y : Enable DMA methods
|
|
CONFIG_USBDEV_MAXPOWER=100 : Maximum power consumption
|
|
CONFIG_USBDEV_SELFPOWERED=y : Self-powered device
|
|
|
|
System Type -> SAMV7 Peripheral Selection
|
|
CONFIG_SAMV7_USBDEVHS=y
|
|
|
|
System Type -> SAMV7 USB High Sppeed Device Controller (DCD options
|
|
For full-speed/low-power mode:
|
|
CONFIG_SAMV7_USBDEVHS_LOWPOWER=y : Select low power mode
|
|
For high-speed/normal mode:
|
|
CONFIG_SAMV7_USBDEVHS_LOWPOWER=n : Don't select low power mode
|
|
CONFIG_SAMV7_USBHS_NDTDS=32 : Number of DMA transfer descriptors
|
|
CONFIG_SAMV7_USBHS_PREALLOCATE=y : Pre-allocate descriptors
|
|
|
|
As discussed in the SAMV71-XULT README, this driver will not work correctly
|
|
if the write back data cache is enabled. You must have:
|
|
|
|
CONFIG_ARMV7M_DCACHE_WRITETHROUGH=y
|
|
|
|
In order to be usable, you must all enabled some class driver(s) for the
|
|
USBHS device controller. Here, for example, is how to configure the CDC/ACM
|
|
serial device class:
|
|
|
|
Device Drivers -> USB Device Driver Support
|
|
CONFIG_CDCACM=y : USB Modem (CDC ACM) support
|
|
CONFIG_CDCACM_EP0MAXPACKET=64 : Enpoint 0 packet size
|
|
CONFIG_CDCACM_EPINTIN=1 : Interrupt IN endpoint number
|
|
CONFIG_CDCACM_EPINTIN_FSSIZE=64 : Full speed packet size
|
|
CONFIG_CDCACM_EPINTIN_HSSIZE=64 : High speed packet size
|
|
CONFIG_CDCACM_EPBULKOUT=3 : Bulk OUT endpoint number
|
|
CONFIG_CDCACM_EPBULKOUT_FSSIZE=64 : Full speed packet size
|
|
CONFIG_CDCACM_EPBULKOUT_HSSIZE=512 : High speed packet size
|
|
CONFIG_CDCACM_EPBULKIN=2 : Bulk IN endpoint number
|
|
CONFIG_CDCACM_EPBULKIN_FSSIZE=64 : Full speed packet size
|
|
CONFIG_CDCACM_EPBULKIN_HSSIZE=512 : High speed packet size
|
|
CONFIG_CDCACM_NWRREQS=4 : Number of write requests
|
|
CONFIG_CDCACM_NRDREQS=8 : Number of read requests
|
|
CONFIG_CDCACM_BULKIN_REQLEN=96 : Size of write request buffer (for full speed)
|
|
CONFIG_CDCACM_BULKIN_REQLEN=768 : Size of write request buffer (for high speed)
|
|
CONFIG_CDCACM_RXBUFSIZE=257 : Serial read buffer size
|
|
CONFIG_CDCACM_TXBUFSIZE=193 : Serial transmit buffer size (for full speed)
|
|
CONFIG_CDCACM_TXBUFSIZE=769 : Serial transmit buffer size (for high speed)
|
|
CONFIG_CDCACM_VENDORID=0x0525 : Vendor ID
|
|
CONFIG_CDCACM_PRODUCTID=0xa4a7 : Product ID
|
|
CONFIG_CDCACM_VENDORSTR="NuttX" : Vendor string
|
|
CONFIG_CDCACM_PRODUCTSTR="CDC/ACM Serial" : Product string
|
|
|
|
Device Drivers -> Serial Driver Support
|
|
CONFIG_SERIAL_REMOVABLE=y : Support for removable serial device
|
|
|
|
The CDC/ACM application provides commands to connect and disconnect the
|
|
CDC/ACM serial device:
|
|
|
|
CONFIG_SYSTEM_CDCACM=y : Enable connect/disconnect support
|
|
CONFIG_SYSTEM_CDCACM_DEVMINOR=0 : Use device /dev/ttyACM0
|
|
CONFIG_CDCACM_RXBUFSIZE=??? : A large RX may be needed
|
|
|
|
If you include this CDC/ACM application, then you can connect the CDC/ACM
|
|
serial device to the host by entering the command 'sercon' and you detach
|
|
the serial device with the command 'serdis'. If you do no use this
|
|
application, they you will have to write logic in your board initialization
|
|
code to initialize and attach the USB device.
|
|
|
|
MCAN1 Loopback Test
|
|
===================
|
|
|
|
MCAN1
|
|
-----
|
|
SAM E70 Xplained has two MCAN modules that performs communication according
|
|
to ISO11898-1 (Bosch CAN specification 2.0 part A,B) and Bosch CAN FD
|
|
specification V1.0. MCAN1 is connected to an on-board ATA6561 CAN physical-layer
|
|
transceiver.
|
|
|
|
------- -------- -------- -------------
|
|
SAM E70 FUNCTION ATA6561 SHARED
|
|
PIN FUNCTION FUNCTIONALITY
|
|
------- -------- -------- -------------
|
|
PC14 CANTX1 TXD Shield
|
|
PC12 CANRX1 RXD Shield
|
|
------- -------- -------- -------------
|
|
|
|
Enabling MCAN1
|
|
--------------
|
|
These modifications may be applied to the same70-xplained/nsh configuration in order
|
|
to enable MCAN1:
|
|
|
|
Device Drivers -> CAN Driver support
|
|
CONFIG_CAN=y # Enable the upper-half CAN driver
|
|
CONFIG_CAN_FIFOSIZE=8
|
|
CONFIG_CAN_NPENDINGRTR=4
|
|
|
|
System Type -> SAMV7 Peripheral Selections
|
|
CONFIG_SAMV7_MCAN1=y # Enable MCAN1 as the lower-half
|
|
|
|
System Type -> MCAN device driver options
|
|
CONFIG_SAMV7_MCAN_CLKSRC_MAIN=y # Use the MAIN clock as the source
|
|
CONFIG_SAMV7_MCAN_CLKSRC_PRESCALER=1
|
|
|
|
System Type ->MCAN device driver options -> MCAN1 device driver options
|
|
CONFIG_SAMV7_MCAN1_ISO11899_1=y # Loopback test only support ISO11899-1
|
|
CONFIG_SAMV7_MCAN1_LOOPBACK=y # Needed for loopback test
|
|
CONFIG_SAMV7_MCAN1_BITRATE=500000 # Not critical for loopback test
|
|
CONFIG_SAMV7_MCAN1_PROPSEG=2 # Bit timing setup
|
|
CONFIG_SAMV7_MCAN1_PHASESEG1=11 # " " " " " "
|
|
CONFIG_SAMV7_MCAN1_PHASESEG2=11 # " " " " " "
|
|
CONFIG_SAMV7_MCAN1_FSJW=4 # " " " " " "
|
|
CONFIG_SAMV7_MCAN1_FBITRATE=2000000 # CAN_FD BTW mode is not used
|
|
CONFIG_SAMV7_MCAN1_FPROPSEG=2 # " " " " " " "" " " " "
|
|
CONFIG_SAMV7_MCAN1_FPHASESEG1=4 # " " " " " " "" " " " "
|
|
CONFIG_SAMV7_MCAN1_FPHASESEG2=4 # " " " " " " "" " " " "
|
|
CONFIG_SAMV7_MCAN1_FFSJW=2 # " " " " " " "" " " " "
|
|
CONFIG_SAMV7_MCAN1_NSTDFILTERS=0 # Filters are not used in the loopback test
|
|
CONFIG_SAMV7_MCAN1_NEXTFILTERS=0 # " " " " " " " " "" " " " " " "
|
|
CONFIG_SAMV7_MCAN1_RXFIFO0_32BYTES=y # Each RX FIFO0 element is 32 bytes
|
|
CONFIG_SAMV7_MCAN1_RXFIFO0_SIZE=8 # There are 8 queue elements
|
|
CONFIG_SAMV7_MCAN1_RXFIFO0_32BYTES=y # Each RX FIFO1 element is 32 bytes
|
|
CONFIG_SAMV7_MCAN1_RXFIFO0_SIZE=8 # There are 8 queue elements
|
|
CONFIG_SAMV7_MCAN1_RXBUFFER_32BYTES=y # Each RX BUFFER is 32 bytes
|
|
CONFIG_SAMV7_MCAN1_TXBUFFER_32BYTES=y # Each TX BUFFER is 32 bytes
|
|
CONFIG_SAMV7_MCAN1_TXFIFOQ_SIZE=8 # There are 8 queue elements
|
|
CONFIG_SAMV7_MCAN1_TXEVENTFIFO_SIZE=0 # The event FIFO is not used
|
|
|
|
Enabling the CAN Loopback Test
|
|
------------------------------
|
|
Application Configuration -> Examples -> CAN Example
|
|
CONFIG_EXAMPLES_CAN=y # Enables the CAN test
|
|
|
|
Enabling CAN Debug Output
|
|
-------------------------
|
|
Build Setup -> Debug Options
|
|
CONFIG_DEBUG_FEATURES=y # Enables general debug features
|
|
CONFIG_DEBUG_INFO=y # Enables verbose output
|
|
CONFIG_DEBUG_CAN_INFO=y # Enables debug output from CAN
|
|
|
|
CONFIG_STACK_COLORATION=y # Monitor stack usage
|
|
CONFIG_DEBUG_SYMBOLS=y # Needed only for use with a debugger
|
|
CONFIG_DEBUG_NOOPT=y # Disables optimization
|
|
|
|
System Type -> MCAN device driver options
|
|
CONFIG_SAMV7_MCAN_REGDEBUG=y # Super low level register debug output
|
|
|
|
SPI Slave
|
|
=========
|
|
|
|
An interrutp driven SPI slave driver as added on 2015-08-09 but has not
|
|
been verified as of this writing. See discussion in include/nuttx/spi/slave.h
|
|
and below.
|
|
|
|
I do not yet have a design that supports SPI slave DMA. And, under
|
|
certain, very limited conditions, I think it can be done. Those
|
|
certain conditions are:
|
|
|
|
a) The master does not tie the chip select to ground. The master must
|
|
raise chip select at the end of the transfer. Then I do not need to
|
|
know the length of the transfer; I can cancel the DMA when the chip
|
|
is de-selected.
|
|
|
|
b) The protocol includes a dummy read after sending the command. This
|
|
is very common in SPI device and should not be an issue if it is
|
|
specified. This dummy read time provides time to set up the DMA.
|
|
So the protocol would be:
|
|
|
|
i) Master drops the chip select.
|
|
ii) Master sends the command which will indicate whether the master
|
|
is reading, writing, or exchanging data. The master discards
|
|
the garbage return value.
|
|
iii) Slave is interrupted when the command word is received. The
|
|
SPI device then decodes the command word and setups up the
|
|
subsequent DMA.
|
|
iv) Master sends a dummy word and discards the return value.
|
|
During the bit times to shift the dummy word, the slave has time
|
|
to set up the DMA.
|
|
v) Master then reads or writes (or exchanges) the data If the DMA
|
|
is in place, the transfer should continue normally.
|
|
vi) At the end of the data transfer the master raises the chip
|
|
select.
|
|
|
|
c) There are limitations in the word time, i.e., the time between the
|
|
interrupt for each word shifted in from the master.
|
|
|
|
The controller driver will get events after the receipt of each word in
|
|
ii), iv), and v). The time between each word will be:
|
|
|
|
word-time = nbits * bit time + inter-word-gap
|
|
|
|
So for an 8 bit interface at 20MHz, the words will be received from the
|
|
master a 8 * 50nsec = 400 nsec + inter-word-gap. That is the time
|
|
during which the dummy word would be shifted and during which we
|
|
receive the interrupt for the command word, interpret the command word,
|
|
and to set up the DMA for the remaining word transfer. I don't think
|
|
that is possible, at least not at 20 MHz.
|
|
|
|
That is far too fast even for the interrupt driven solution that I have
|
|
in place now. It could not work at 20MHz. If we suppose that interrupt
|
|
processing is around 1 usec, then an 8 bit interface could not have bit
|
|
times more than 125 nsec or 8 KHz. Interrupt handling should be faster
|
|
than 1 usec, but not a lot faster. I have not benchmarked it. NuttX
|
|
also supports special, zero latency interrupts that could bring the
|
|
interrupt time down even more.
|
|
|
|
Note that we would also have a little more processing time if you used
|
|
16-bit SPI word size.
|
|
|
|
Note also that the interrupt driven approach would have this same basic
|
|
performance limitation with the additional disadvantage that:
|
|
|
|
a) The driver will receive two interrupts per word exchanged:
|
|
|
|
i) One interrupt will be received when the word is shifted in from
|
|
the master (at the end of 8-bit times). This is a data received
|
|
interrupt.
|
|
|
|
ii) And another interrupt when the next words moved to the shift-out
|
|
register, freeing up the transmit holding register. This is the
|
|
data sent interrupt.
|
|
|
|
The ii) event should be very soon after the i) event.
|
|
|
|
Without DMA, the only way to reduce the interrupt rate would be to add
|
|
interrupt-level polling to detect the when transmit holding register
|
|
is available. That is not really a good idea.
|
|
|
|
b) It will hog all of the CPU for the duration of the transfer).
|
|
|
|
Click Shield
|
|
============
|
|
|
|
In the mrf24j40-starhub configuration, a click shield from
|
|
MikroElectronika was used along with a Click "Bee" module. The click
|
|
shield supports two click shields and the following tables describe the
|
|
relationship between the pins on each click shield, the Arduino
|
|
connector and the SAME70 pins.
|
|
|
|
--------- ---------------------- -------- --------- ------------------ ----------
|
|
mikroBUS1 Arduino SAME70 mikroBUS2 Arduino SAME70
|
|
--------- ---------------------- -------- --------- ------------------ ----------
|
|
AN HD1 A0 AN0 Pin 1 AD0 PD26 AN HD1 A1 AN1 Pin 2 AD1 PC31
|
|
RST HD1 A3 Pin 4 AD3 PA19 RST HD1 A2 Pin 3 AD2 PD30
|
|
CS HD4 D10 SPI-SS Pin 8 D10 PD25 CS HD4 D9 Pin 9 D9 PC9
|
|
SCK HD4 D13 SPI-SCK Pin 5 D13 PD22 SCK Same
|
|
MISO HD4 D12 SPI-MISO Pin 6 D12 PD20 MISO Same
|
|
MOSI HD4 D11 SPI-MOSI Pin 7 D11 PD21 MOSI Same
|
|
3.3V N/A 3.3V N/A
|
|
GND N/A GND N/A
|
|
PWM HD3 D6 PWMA Pin 2 D6 PC19 PWM HD3 D5 PWMB Pin 5 D5 PD11
|
|
INT HD3 D2 INT0 Pin 6 D2 PA5 INT HD3 D3 INT1 Pin 5 D3 PA6
|
|
RX HD3 D0 HDR-RX* Pin 8 D0 PD28 RX Same
|
|
TX HD3 D1 HDR-TX* Pin 7 D1 PD30 TX Same
|
|
SCL HD1 A5 I2C-SCL Pin 5 AD5 PC30 SDA Same
|
|
SDA HD1 A4 I2C-SDA Pin 6 AD4 PC13 SCL Same
|
|
5V N/A 5V N/A
|
|
GND N/A GND N/A
|
|
--------- ---------------------- -------- --------- ------------------ ----------
|
|
|
|
* Depends upon setting of SW1, UART vs PROG.
|
|
|
|
--- ----- ------------------------------ ---------------------------------
|
|
PIN PORT SHIELD FUNCTION SAME70PIN CONFIGURATION
|
|
--- ----- ------------------------------ ---------------------------------
|
|
AD0 PD26 microBUS2 Analog TD PD26 *** Not an AFE pin ***
|
|
AD1 PC31 microBUS2 Analog PC31 AFE1_AD6 GPIO_AFE1_AD6
|
|
AD2 PD30 microBUS2 GPIO reset output PD30
|
|
AD3 PA19 microBUS1 GPIO reset output PA19
|
|
AD4 PC13 (both) I2C-SDA PC13 *** Does not support I2C SDA ***
|
|
AD5 PC30 (both) I2C-SCL PC30 *** Does not support I2C SCL ***
|
|
AD6 PA17 *** Not used ***
|
|
AD7 PC12 *** Not used ***
|
|
D0 PD28 (both) HDR_RX PD28 URXD3 GPIO_UART3_RXD
|
|
D1 PD30 (both) HDR_TX PD30 UTXD3 GPIO_UART3_TXD_1
|
|
D2 PA5 microBUS1 GPIO interrupt input PA5
|
|
D3 PA6 microBUS2 GPIO interrupt input PA6
|
|
D4 PD27 *** Not used ***
|
|
D5 PD11 microBUS2 PWMB PD11 PWMC0_H0
|
|
D6 PC19 microBUS1 PWMA PC19 PWMC0_H2
|
|
D7 PA2 *** Not used ***
|
|
D8 PA17 *** Not used ***
|
|
D9 PC9 microBUS2 CS GPIO output PC9
|
|
D10 PD25 microBUS1 CS GPIO output PD25 SPI0_NPCS1
|
|
D11 PD21 (both) SPI-MOSI PD21 SPI0_MOSI GPIO_SPI0_MOSI
|
|
D12 PD20 (both) SPI-MISO PD20 SPI0_MISO GPIO_SPI0_MISO
|
|
D13 PD22 (both) SPI-SCK PD22 SPI0_SPCK GPIO_SPI0_SPCK
|
|
|
|
NOTE: The click shield fits close to the Arduino connect and cannot be
|
|
installed directly because it hits the RJ45 connector. You have to get
|
|
some extra Arduino connectors to raise the Click shield so that it clears
|
|
the RJ45.
|
|
|
|
This may be a problem only for me because the Arduino connectors that I
|
|
soldered onto the SAME70-Xplained are short (around 10mm clearance from
|
|
the board). Taller headers might clear the RJ45 connector (around 15mm).
|
|
|
|
NOTE: Mikroelektronika provides two different click shields: A UNO style
|
|
shield with two click mikroBUSes and a larger Mega shield with three
|
|
click mikroBUSes. The above discusses on the UNO shield. I know that the
|
|
serial ports, at least, differ on the two shields.
|
|
|
|
UPDATE: And it appears the that Mega shield is *not* compatible with the
|
|
SAME70-Xplained. I am told that the SPI in mikroBUS slots does not connect
|
|
to pins on the SAME70-Xplained that can support the SPI communications.
|
|
Avoid this triple mikroBUS shield!
|
|
|
|
Tickless OS
|
|
===========
|
|
|
|
Background
|
|
----------
|
|
By default, a NuttX configuration uses a periodic timer interrupt that
|
|
drives all system timing. The timer is provided by architecture-specific
|
|
code that calls into NuttX at a rate controlled by CONFIG_USEC_PER_TICK.
|
|
The default value of CONFIG_USEC_PER_TICK is 10000 microseconds which
|
|
corresponds to a timer interrupt rate of 100 Hz.
|
|
|
|
An option is to configure NuttX to operation in a "tickless" mode. Some
|
|
limitations of default system timer are, in increasing order of
|
|
importance:
|
|
|
|
- Overhead: Although the CPU usage of the system timer interrupt at 100Hz
|
|
is really very low, it is still mostly wasted processing time. One most
|
|
timer interrupts, there is really nothing that needs be done other than
|
|
incrementing the counter.
|
|
- Resolution: Resolution of all system timing is also determined by
|
|
CONFIG_USEC_PER_TICK. So nothing that be time with resolution finer than
|
|
10 milliseconds be default. To increase this resolution,
|
|
CONFIG_USEC_PER_TICK an be reduced. However, then the system timer
|
|
interrupts use more of the CPU bandwidth processing useless interrupts.
|
|
- Power Usage: But the biggest issue is power usage. When the system is
|
|
IDLE, it enters a light, low-power mode (for ARMs, this mode is entered
|
|
with the wfi or wfe instructions for example). But each interrupt
|
|
awakens the system from this low power mode. Therefore, higher rates
|
|
of interrupts cause greater power consumption.
|
|
|
|
The so-called Tickless OS provides one solution to issue. The basic
|
|
concept here is that the periodic, timer interrupt is eliminated and
|
|
replaced with a one-shot, interval timer. It becomes event driven
|
|
instead of polled: The default system timer is a polled design. On
|
|
each interrupt, the NuttX logic checks if it needs to do anything
|
|
and, if so, it does it.
|
|
|
|
Using an interval timer, one can anticipate when the next interesting
|
|
OS event will occur, program the interval time and wait for it to fire.
|
|
When the interval time fires, then the scheduled activity is performed.
|
|
|
|
Configuration
|
|
-------------
|
|
The following configuration options will enable support for the Tickless
|
|
OS for the SAMV7 platforms using TC0 channels 0-3 (other timers or
|
|
timer channels could be used making the obvious substitutions):
|
|
|
|
RTOS Features -> Clocks and Timers
|
|
CONFIG_SCHED_TICKLESS=y : Configures the RTOS in tickless mode
|
|
CONFIG_SCHED_TICKLESS_ALARM=n : (option not implemented)
|
|
CONFIG_SCHED_TICKLESS_LIMIT_MAX_SLEEP=y
|
|
|
|
System Type -> SAMV7 Peripheral Support
|
|
CONFIG_SAMV7_TC0=y : Enable TC0 (TC channels 0-3
|
|
|
|
System Type -> Timer/counter Configuration
|
|
CONFIG_SAMV7_ONESHOT=y : Enables one-shot timer wrapper
|
|
CONFIG_SAMV7_FREERUN=y : Enabled free-running timer wrapper
|
|
CONFIG_SAMV7_TICKLESS_ONESHOT=0 : Selects TC0 channel 0 for the one-shot
|
|
CONFIG_SAMV7_TICKLESS_FREERUN=1 : Selects TC0 channel 1 for the free-
|
|
: running timer
|
|
|
|
The resolution of the clock is provided by the CONFIG_USEC_PER_TICK
|
|
setting in the configuration file.
|
|
|
|
NOTE: In most cases, the slow clock will be used as the timer/counter
|
|
input. The SAME70-Xplained board has pads for a 32.768KHz crystal,
|
|
however, the boad ships with that position unpopulated. So, be default
|
|
this will probably end up using the slow RC oscillator which will give
|
|
you very bad timing.
|
|
|
|
If you add a crystal to your board, you can select to use it with the
|
|
definition BOARD_HAVE_SLOWXTAL in the configs/same70-xplained/board.h
|
|
file.
|
|
|
|
The slow clock has a resolution of about 30.518 microseconds. Ideally,
|
|
the value of CONFIG_USEC_PER_TICK should be the exact clock resolution.
|
|
Otherwise there will be cumulative timing inaccuracies. But a choice
|
|
choice of:
|
|
|
|
CONFIG_USEC_PER_TICK=31
|
|
|
|
will have an error of 0.6% and will have inaccuracies that will
|
|
effect the time due to long term error build-up.
|
|
|
|
Using the slow clock input, the Tickless support is functional,
|
|
however, there are inaccuracies in delays. For example,
|
|
|
|
nsh> sleep 10
|
|
|
|
results in a delay of maybe 5.4 seconds. But the timing accuracy is
|
|
correct if all competing uses of the interval timer are disabled (mostly
|
|
from the high priority work queue). Therefore, I conclude that this
|
|
inaccuracy is due to the inaccuracies in the representation of the clock
|
|
rate. 30.518 usec cannot be represented accurately. Each timing
|
|
calculation results in a small error. When the interval timer is very
|
|
busy, long delays will be divided into many small pieces and each small
|
|
piece has a large error in the calculation. The cumulative error is the
|
|
cause of the problem.
|
|
|
|
Solution: The same70-xplained/src/sam_boot.c file has additional logic
|
|
to enable the programmable clock PCK6 as a clock source for the
|
|
timer/counters if the Tickless mode is selected. The ideal frequency
|
|
would be:
|
|
|
|
frequency = 1,000,000 / CONFIG_USEC_PER_TICK
|
|
|
|
The main crystal is selected as the frequency source. The maximum
|
|
prescaler value is 256 so the minimum frequency is 46,875 Hz which
|
|
corresponds to a period of 21.3 microseconds. A value of
|
|
CONFIG_USEC_PER_TICK=20, or 50KHz, would give an exact solution with
|
|
a divider of 240.
|
|
|
|
SAME70 Timer Usage
|
|
------------------
|
|
This current implementation uses two timers: A one-shot timer to
|
|
provide the timed events and a free running timer to provide the current
|
|
time. Since timers are a limited resource, that could be an issue on
|
|
some systems.
|
|
|
|
We could do the job with a single timer if we were to keep the single
|
|
timer in a free-running at all times. The SAME70 timer/counters have
|
|
16-bit counters with the capability to generate a compare interrupt when
|
|
the timer matches a compare value but also to continue counting without
|
|
stopping (giving another, different interrupt when the timer rolls over
|
|
from 0xffff to zero). So we could potentially just set the compare at
|
|
the number of ticks you want PLUS the current value of timer. Then you
|
|
could have both with a single timer: An interval timer and a free-
|
|
running counter with the same timer! In this case, you would want to
|
|
to set CONFIG_SCHED_TICKLESS_ALARM in the NuttX configuration.
|
|
|
|
Patches are welcome!
|
|
|
|
Debugging
|
|
=========
|
|
|
|
EDBG
|
|
----
|
|
The on-board EDBG appears to work only with Atmel Studio. You can however,
|
|
simply connect a SAM-ICE or J-Link to the JTAG/SWD connector on the board
|
|
and that works great. The only tricky thing is getting the correct
|
|
orientation of the JTAG connection.
|
|
|
|
J-Link/JTAG
|
|
-----------
|
|
I have been using Atmel Studio to write code to flash then I use the Segger
|
|
J-Link GDB server to debug. I have been using the 'Device Programming' I
|
|
available under the Atmel Studio 'Tool' menu. I have to disconnect the
|
|
SAM-ICE while programming with the EDBG. I am sure that you could come up
|
|
with a GDB server-only solution if you wanted.
|
|
|
|
I run GDB like this from the directory containing the NuttX ELF file:
|
|
|
|
arm-none-eabi-gdb
|
|
(gdb) target remote localhost:2331
|
|
(gdb) mon reset
|
|
(gdb) file nuttx
|
|
(gdb) ... start debugging ...
|
|
|
|
OpenOCD/EDBG
|
|
------------
|
|
Current OpenOCD also works with SAME70-Xplained via EDBG, but I have not
|
|
used OpenOCD with the board.
|
|
|
|
SAM-BA
|
|
------
|
|
SAM-BA is another option. With SAM-BA, you can load code into FLASH over
|
|
a serial port or USB connection by booting into the ROM bootloader.
|
|
|
|
CMSIS-DAP Programmer
|
|
--------------------
|
|
Another useful tool for CMSIS-DAP programmer (formerly Atmel EDBG
|
|
programmer) available at:
|
|
|
|
https://github.com/ataradov/edbg
|
|
|
|
This is a simple command line utility for programming ARM-based MCUs
|
|
(currently only Atmel) though CMSIS-DAP SWD interface. It works on Linux,
|
|
Mac OS X and Windows. Very useful to around especially if you have the
|
|
following issue:
|
|
|
|
Booting to FLASH or the ROM Bootloader
|
|
--------------------------------------
|
|
If you use EDBG or JTAG to load code into FLASH, you may be puzzled why
|
|
the code does not run. It may be that you are booting into the ROM
|
|
bootloader instead of FLASH. That can be fixed by modifying the SAME70's
|
|
GPNVM bits.
|
|
|
|
If your SAME70 is booting in ROM by default, the GPNVM bits will probably
|
|
looking something like:
|
|
|
|
$ edbg.exe -F r,:, -t atmel_cm7
|
|
GPNVM Bits: 0x40
|
|
|
|
Where bit 1 = 0 boots into the ROM bootloader and bit 1 = 1 boots into
|
|
FLASH. You want:
|
|
|
|
$ edbg.exe -F r,:, -t atmel_cm7
|
|
GPNVM Bits: 0x42
|
|
|
|
If you are trying to use SAM-BA, you might have the opposity problem:
|
|
The board might be booting into FLASH when you need it to boot into the
|
|
ROM bootloader.
|
|
|
|
That GPNVM bit can be changed using CMSIS-DAP programmer, Atmel studio, or
|
|
using this OpenOCD setup:
|
|
|
|
atsamv gpnvm [('clr'|'set'|'show') bitnum]
|
|
Without arguments, shows all bits in the gpnvm register.
|
|
Otherwise, clears, sets, or shows one General Purpose Non-Volatile
|
|
Memory (gpnvm) bit.
|
|
|
|
Perhaps SAM-BA supports a way to do this as well???
|
|
|
|
Using OpenOCD and GDB to flash via the EDBG chip
|
|
================================================
|
|
|
|
Building OpenOCD under Cygwin:
|
|
|
|
Refer to configs/olimex-lpc1766stk/README.txt
|
|
|
|
Installing OpenOCD in Linux (but see note below):
|
|
|
|
sudo apt-get install openocd
|
|
|
|
NOTE: At the time of writing installing the above openocd package from
|
|
the distribution (Ubuntu 14.04) was not enough to get the latest openocd
|
|
version supporting the SAME70 Xplained.
|
|
|
|
The code was obtained from the OpenOCD git repository, available at
|
|
https://github.com/ntfreak/openocd.
|
|
|
|
git clone https://github.com/ntfreak/openocd.git
|
|
|
|
Then follow the directions of the "Building OpenOCD" section of their README,
|
|
but be sure to configure including the CMSIS-DAP interface:
|
|
|
|
./bootstrap
|
|
./configure --enable-cmsis-dap
|
|
make
|
|
sudo make install
|
|
|
|
If your configure step fails, you might be missing some dependencies, i.e.:
|
|
|
|
sudo apt-get install libhidapi-dev
|
|
|
|
Helper Scripts.
|
|
|
|
OpenOCD requires a configuration file. I keep the one I used last here:
|
|
|
|
configs/same70-xplained/tools/atmel_same70_xplained.cfg
|
|
|
|
However, the "correct" configuration script to use with OpenOCD may
|
|
change as the features of OpenOCD evolve. So you should at least
|
|
compare that atmel_same70_xplained.cfg file with configuration files in
|
|
/usr/share/openocd/scripts. As of this writing, the configuration
|
|
files of interest were:
|
|
|
|
/usr/share/openocd/scripts/interface/cmsis-dap.cfg
|
|
/usr/share/openocd/scripts/board/atmel_same70_xplained.cfg
|
|
/usr/share/openocd/scripts/target/atsamv.cfg
|
|
|
|
There is also a script on the tools/ directory that I use to start
|
|
the OpenOCD daemon on my system called oocd.sh. That script will
|
|
probably require some modifications to work in another environment:
|
|
|
|
- Possibly the value of OPENOCD_PATH and TARGET_PATH
|
|
- It assumes that the correct script to use is the one at
|
|
configs/same70-xplained/tools/atmel_same70_xplained.cfg
|
|
|
|
Starting OpenOCD
|
|
|
|
Then you should be able to start the OpenOCD daemon like:
|
|
|
|
configs/same70-xplained/tools/oocd.sh $PWD
|
|
|
|
Connecting GDB
|
|
|
|
Once the OpenOCD daemon has been started, you can connect to it via
|
|
GDB using the following GDB command:
|
|
|
|
arm-nuttx-elf-gdb
|
|
(gdb) target remote localhost:3333
|
|
|
|
NOTE: The name of your GDB program may differ. For example, with the
|
|
CodeSourcery toolchain, the ARM GDB would be called arm-none-eabi-gdb.
|
|
|
|
After starting GDB, you can load the NuttX ELF file:
|
|
|
|
(gdb) symbol-file nuttx
|
|
(gdb) monitor reset
|
|
(gdb) monitor halt
|
|
(gdb) load nuttx
|
|
|
|
NOTES:
|
|
1. Loading the symbol-file is only useful if you have built NuttX to
|
|
include debug symbols (by setting CONFIG_DEBUG_SYMBOLS=y in the
|
|
.config file).
|
|
2. The MCU must be halted prior to loading code using 'mon reset'
|
|
as described below.
|
|
|
|
OpenOCD will support several special 'monitor' commands. These
|
|
GDB commands will send comments to the OpenOCD monitor. Here
|
|
are a couple that you will need to use:
|
|
|
|
(gdb) monitor reset
|
|
(gdb) monitor halt
|
|
|
|
NOTES:
|
|
1. The MCU must be halted using 'mon halt' prior to loading code.
|
|
2. Reset will restart the processor after loading code.
|
|
3. The 'monitor' command can be abbreviated as just 'mon'.
|
|
|
|
Configurations
|
|
==============
|
|
|
|
Information Common to All Configurations
|
|
----------------------------------------
|
|
Each SAME70-XPLD configuration is maintained in a sub-directory and
|
|
can be selected as follow:
|
|
|
|
cd tools
|
|
./configure.sh same70-xplained/<subdir>
|
|
cd -
|
|
|
|
Before building, make sure that the PATH environment variable include the
|
|
correct path to the directory than holds your toolchain binaries.
|
|
|
|
And then build NuttX by simply typing the following. At the conclusion of
|
|
the make, the nuttx binary will reside in an ELF file called, simply, nuttx.
|
|
|
|
make oldconfig
|
|
make
|
|
|
|
The <subdir> that is provided above as an argument to the tools/configure.sh
|
|
must be is one of the following.
|
|
|
|
NOTES:
|
|
|
|
1. These configurations use the mconf-based configuration tool. To
|
|
change any of these configurations using that tool, you should:
|
|
|
|
a. Build and install the kconfig-mconf tool. See nuttx/README.txt
|
|
see additional README.txt files in the NuttX tools repository.
|
|
|
|
b. Execute 'make menuconfig' in nuttx/ in order to start the
|
|
reconfiguration process.
|
|
|
|
2. Unless stated otherwise, all configurations generate console
|
|
output on USART1 (the EDBG VCOM)
|
|
|
|
NOTE: When USART1 is used, the pin PB4 is reconfigured. Normally, PB4
|
|
is TDI. When it is reconfigured for use with USART1, the capability to
|
|
debug is lost! If you plan to debug you should most certainly not use
|
|
USART1. UART3 might be a good option (the Arduino RXD/TXD):
|
|
|
|
-CONFIG_SAMV7_USART1=y
|
|
-CONFIG_USART1_SERIALDRIVER=y
|
|
-CONFIG_USART1_SERIAL_CONSOLE=y
|
|
-CONFIG_USART1_RXBUFSIZE=256
|
|
-CONFIG_USART1_TXBUFSIZE=256
|
|
-CONFIG_USART1_BAUD=115200
|
|
-CONFIG_USART1_BITS=8
|
|
-CONFIG_USART1_PARITY=0
|
|
-CONFIG_USART1_2STOP=0
|
|
|
|
+CONFIG_SAMV7_UART3=y
|
|
+CONFIG_UART3_SERIAL_CONSOLE=y
|
|
+CONFIG_UART3_RXBUFSIZE=256
|
|
+CONFIG_UART3_TXBUFSIZE=256
|
|
+CONFIG_UART3_BAUD=115200
|
|
+CONFIG_UART3_BITS=8
|
|
+CONFIG_UART3_PARITY=0
|
|
+CONFIG_UART3_2STOP=0
|
|
|
|
UART3 is not the default because (1) the placement of the RJ-45 connector
|
|
makes it difficult to install Arduino shield cards and (2) the Arduino
|
|
connectors are not populated on the board as it comes from the factory.
|
|
|
|
3. All of these configurations are set up to build under Windows using the
|
|
"GNU Tools for ARM Embedded Processors" that is maintained by ARM
|
|
(unless stated otherwise in the description of the configuration).
|
|
|
|
https://developer.arm.com/open-source/gnu-toolchain/gnu-rm
|
|
|
|
That toolchain selection can easily be reconfigured using
|
|
'make menuconfig'. Here are the relevant current settings:
|
|
|
|
Build Setup:
|
|
CONFIG_HOST_WINDOWS=y : Window environment
|
|
CONFIG_WINDOWS_CYGWIN=y : Cywin under Windows
|
|
|
|
System Type -> Toolchain:
|
|
CONFIG_ARMV7M_TOOLCHAIN_GNU_EABIW=y : GNU ARM EABI toolchain
|
|
|
|
NOTE: As of this writing, there are issues with using this tool at
|
|
the -Os level of optimization. This has not been proven to be a
|
|
compiler issue (as least not one that might not be fixed with a
|
|
well placed volatile qualifier). However, in any event, it is
|
|
recommend that you use not more that -O2 optimization.
|
|
|
|
Configuration sub-directories
|
|
-----------------------------
|
|
|
|
mrf24j40-starhub
|
|
|
|
This configuration implements a hub node in a 6LoWPAN start network.
|
|
It is intended for the us the mrf24j40-starpoint configuration with
|
|
the clicker2-stm32 configurations. Essentially, the SAME70 Xplained
|
|
plays the roll of the hub in the configuration and the clicker2-stm32
|
|
boards are the endpoints in the start.
|
|
|
|
NOTES:
|
|
|
|
1. The serial console is configured by default for use with and Arduino
|
|
serial shield (UART3). You will need to reconfigure if you will
|
|
to use a different U[S]ART.
|
|
|
|
2. This configuration derives from the netnsh configuration, but adds
|
|
support for IPv6, 6LoWPAN, and the MRF24J40 IEEE 802.15.4 radio.
|
|
|
|
3. This configuration uses the Mikroe BEE MRF24j40 click boards and
|
|
connects to the SAMV71-XULT using a click shield as described above.
|
|
|
|
4. You must must have also have at least two clicker2-stm32 boards each
|
|
with an MRF24J40 BEE click board in order to run these tests.
|
|
|
|
5. The network initialization thread is NOT enabled. As a result, the
|
|
startup will hang if the Ethernet cable is not plugged in. For more
|
|
information, see the paragraphs above entitled "Network Initialization
|
|
Thread" and "Network Monitor".
|
|
|
|
6. Telnet: The clicker2-stm32 star point configuration supports the
|
|
Telnet daemon, but not the Telnet client; the star hub configuration
|
|
supports both the Telnet client and the Telnet daemon. Therefore,
|
|
the star hub can Telnet to any point in the star, but the star
|
|
endpoints cannot initiate telnet sessions. Any host connected via
|
|
Ethernet can Telnet to the SAME70 Xplained hub or to any Clicker2
|
|
point in the star.
|
|
|
|
7. TCP and UDP Tests: The same TCP and UDP tests as described for
|
|
the clicker2-stm32 mrf24j40-starpoint configuration are supported on
|
|
the star endpoints, but NOT on the star hub. Therefore, all network
|
|
testing is between endpoints with the hub acting, well, only like a
|
|
hub.
|
|
|
|
The nsh> dmesg command can be use at any time on any endpoint node
|
|
to see any debug output that you have selected. Debug output on the
|
|
hub will be presented on stdout.
|
|
|
|
Telenet sessions may be initiated only from the hub to a star
|
|
endpoint:
|
|
|
|
C: nsh> telnet <server-ip> <-- Runs the Telnet client
|
|
|
|
Where <server-ip> is the IP address of either the E1 or I2 endpoints.
|
|
|
|
STATUS:
|
|
2017-08-16: Configurations added. Initially, I saw hangs i
|
|
mrf24j40_reset() before the NSH appears on the serial console.
|
|
Unlike the SAMV71-XULT, the SPI looks clean, but was hanging
|
|
nevertheless.
|
|
|
|
Then, on subsequent testing, it "magically" started behaving
|
|
properaly and seems quite stable now.. although I did nothing to
|
|
solve the problem. Perhaps the radio was in a bad state for awhile;
|
|
perhaps something I did masked the problem. However, all is well
|
|
for the time being.
|
|
|
|
No significant functional testing has yet been performed.
|
|
|
|
2017-08-26: There was only a single buffer for reassemblying larger
|
|
packets. This could be a problem issue for the hub configuration
|
|
which really needs the capability concurrently reassemble multiple
|
|
incoming streams. The design was extended to support multiple
|
|
reassembly buffers but have not yet been verified on this platform.
|
|
|
|
netnsh:
|
|
|
|
Configures the NuttShell (nsh) located at examples/nsh. There are two
|
|
very similar NSH configurations:
|
|
|
|
- nsh. This configuration is focused on low level, command-line
|
|
driver testing. It has no network.
|
|
- netnsh. This configuration is focused on network testing and
|
|
has only limited command support.
|
|
|
|
NOTES:
|
|
|
|
1. The serial console is configured by default for use with the EDBG VCOM
|
|
(USART1). You will need to reconfigure if you will to use a different
|
|
U[S]ART. See "Information Common to All Configurations" above.
|
|
|
|
2. Default stack sizes are large and should really be tuned to reduce
|
|
the RAM footprint:
|
|
|
|
CONFIG_SCHED_HPWORKSTACKSIZE=2048
|
|
CONFIG_IDLETHREAD_STACKSIZE=1024
|
|
CONFIG_USERMAIN_STACKSIZE=2048
|
|
CONFIG_PTHREAD_STACK_MIN=256
|
|
CONFIG_PTHREAD_STACK_DEFAULT=2048
|
|
CONFIG_POSIX_SPAWN_PROXY_STACKSIZE=1024
|
|
CONFIG_TASK_SPAWN_DEFAULT_STACKSIZE=2048
|
|
CONFIG_BUILTIN_PROXY_STACKSIZE=1024
|
|
CONFIG_NSH_TELNETD_DAEMONSTACKSIZE=2048
|
|
CONFIG_NSH_TELNETD_CLIENTSTACKSIZE=2048
|
|
|
|
3. NSH built-in applications are supported. There are, however, not
|
|
enabled built-in applications.
|
|
|
|
Binary Formats:
|
|
CONFIG_BUILTIN=y : Enable support for built-in programs
|
|
|
|
Application Configuration:
|
|
CONFIG_NSH_BUILTIN_APPS=y : Enable starting apps from NSH command line
|
|
|
|
4. The network initialization thread and the NSH network montior are
|
|
enabled in this configuration. As a result, networking initialization
|
|
is performed asynchronously with NSH bring-up. For more information,
|
|
see the paragraphs above entitled "Network Initialization Thread" and
|
|
"Network Monitor".
|
|
|
|
5. SDRAM is NOT enabled in this configuration.
|
|
|
|
6. TWI/I2C
|
|
|
|
TWIHS0 is enabled in this configuration. The SAM E70 Xplained
|
|
supports one devices on the one on-board I2C device on the TWIHS0 bus:
|
|
The AT24MAC402 serial EEPROM described above.
|
|
Relevant configuration settings:
|
|
|
|
CONFIG_SAMV7_TWIHS0=y
|
|
CONFIG_SAMV7_TWIHS0_FREQUENCY=100000
|
|
|
|
CONFIG_I2C=y
|
|
|
|
7. TWIHS0 is used to support 256 byte non-volatile storage. This EEPROM
|
|
holds the assigned MAC address which is necessary for networking. The
|
|
EEPROM is also available for storage of configuration data using the
|
|
MTD configuration as described above under the heading, "MTD
|
|
Configuration Data".
|
|
|
|
8. Support for HSMCI is built-in by default. The SAME70-XPLD provides
|
|
one full-size SD memory card slot. Refer to the section entitled
|
|
"SD card" for configuration-related information.
|
|
|
|
See "Open Issues" above for issues related to HSMCI.
|
|
|
|
The auto-mounter is not enabled. See the section above entitled
|
|
"Auto-Mounter".
|
|
|
|
9. Performance-related Configuration settings:
|
|
|
|
CONFIG_ARMV7M_ICACHE=y : Instruction cache is enabled
|
|
CONFIG_ARMV7M_DCACHE=y : Data cache is enabled
|
|
CONFIG_ARMV7M_DCACHE_WRITETHROUGH=y : Write through mode
|
|
CONFIG_ARCH_FPU=y : H/W floating point support is enabled
|
|
CONFIG_ARCH_DPFPU=y : 64-bit H/W floating point support is enabled
|
|
|
|
# CONFIG_ARMV7M_ITCM is not set : Support not yet in place
|
|
# CONFIG_ARMV7M_DTCM is not set : Support not yet in place
|
|
|
|
I- and D-Caches are enabled but the D-Cache must be enabled in write-
|
|
through mode. This is to work around issues with the RX and TX
|
|
descriptors with are 8-bytes in size. But the D-Cache cache line
|
|
size is 32-bytes. That means that you cannot reload, clean or
|
|
invalidate a descriptor without also effecting three neighboring
|
|
descriptors. Setting write through mode eliminates the need for
|
|
cleaning the D-Cache. If only reloading and invalidating are done,
|
|
then there is no problem.
|
|
|
|
Stack sizes are also large to simplify the bring-up and should be
|
|
tuned for better memory usages.
|
|
|
|
STATUS:
|
|
2015-03-29: I- and D-caches are currently enabled, but as noted
|
|
above, the D-Cache must be enabled in write-through mode. Also -Os
|
|
optimization is not being used (-O2). If the cache is enabled in
|
|
Write-Back mode or if higher levels of optimization are enabled, then
|
|
there are failures when trying to ping the target from a host.
|
|
|
|
nsh:
|
|
|
|
Configures the NuttShell (nsh) located at examples/nsh. There are two
|
|
very similar NSH configurations:
|
|
|
|
- nsh. This configuration is focused on low level, command-line
|
|
driver testing. It has no network.
|
|
- netnsh. This configuration is focused on network testing and
|
|
has only limited command support.
|
|
|
|
NOTES:
|
|
|
|
1. The serial console is configured by default for use with the EDBG VCOM
|
|
(USART1). You will need to reconfigure if you will to use a different
|
|
U[S]ART. See "Information Common to All Configurations" above.
|
|
|
|
2. Default stack sizes are large and should really be tuned to reduce
|
|
the RAM footprint:
|
|
|
|
CONFIG_ARCH_INTERRUPTSTACK=2048
|
|
CONFIG_IDLETHREAD_STACKSIZE=1024
|
|
CONFIG_USERMAIN_STACKSIZE=2048
|
|
CONFIG_PTHREAD_STACK_DEFAULT=2048
|
|
... and others ...
|
|
|
|
3. NSH built-in applications are supported.
|
|
|
|
Binary Formats:
|
|
CONFIG_BUILTIN=y : Enable support for built-in programs
|
|
|
|
Application Configuration:
|
|
CONFIG_NSH_BUILTIN_APPS=y : Enable starting apps from NSH command line
|
|
|
|
4. SDRAM is enabled in this configuration. Here are the relevant
|
|
configuration settings:
|
|
|
|
System Type
|
|
CONFIG_SAMV7_SDRAMC=y
|
|
CONFIG_SAMV7_SDRAMSIZE=2097152
|
|
|
|
SDRAM is not added to the heap in this configuration. To do that
|
|
you would need to set CONFIG_SAMV7_SDRAMHEAP=y and CONFIG_MM_REGIONS=2.
|
|
Instead, the SDRAM is set up so that is can be used with a destructive
|
|
RAM test enabled with this option:
|
|
|
|
Application Configuration:
|
|
CONFIG_SYSTEM_RAMTEST=y
|
|
|
|
The RAM test can be executed as follows:
|
|
|
|
nsh> ramtest -w 70000000 2097152
|
|
|
|
NuttShell (NSH) NuttX-7.8
|
|
nsh> ramtest -w 70000000 2097152
|
|
RAMTest: Marching ones: 70000000 2097152
|
|
RAMTest: Marching zeroes: 70000000 2097152
|
|
RAMTest: Pattern test: 70000000 2097152 55555555 aaaaaaaa
|
|
RAMTest: Pattern test: 70000000 2097152 66666666 99999999
|
|
RAMTest: Pattern test: 70000000 2097152 33333333 cccccccc
|
|
RAMTest: Address-in-address test: 70000000 2097152
|
|
nsh>
|
|
|
|
5. TWI/I2C
|
|
|
|
TWIHS0 is enabled in this configuration. The SAM E70 Xplained
|
|
supports one device on the one on-board I2C device on the TWIHS0 bus:
|
|
The AT24MAC402 serial EEPROM described above.
|
|
|
|
In this configuration, the I2C tool at apps/system/i2ctool is
|
|
enabled. This tools supports interactive access to I2C devices on
|
|
the enabled TWIHS bus. Relevant configuration settings:
|
|
|
|
CONFIG_SAMV7_TWIHS0=y
|
|
CONFIG_SAMV7_TWIHS0_FREQUENCY=100000
|
|
|
|
CONFIG_I2C=y
|
|
|
|
CONFIG_SYSTEM_I2CTOOL=y
|
|
CONFIG_I2CTOOL_MINBUS=0
|
|
CONFIG_I2CTOOL_MAXBUS=0
|
|
CONFIG_I2CTOOL_MINADDR=0x03
|
|
CONFIG_I2CTOOL_MAXADDR=0x77
|
|
CONFIG_I2CTOOL_MAXREGADDR=0xff
|
|
CONFIG_I2CTOOL_DEFFREQ=400000
|
|
|
|
Example usage:
|
|
|
|
nsh> i2c
|
|
Usage: i2c <cmd> [arguments]
|
|
Where <cmd> is one of:
|
|
|
|
Show help : ?
|
|
List busses : bus
|
|
List devices : dev [OPTIONS] <first> <last>
|
|
Read register : get [OPTIONS] [<repititions>]
|
|
Show help : help
|
|
Write register: set [OPTIONS] <value> [<repititions>]
|
|
Verify access : verf [OPTIONS] [<value>] [<repititions>]
|
|
|
|
Where common "sticky" OPTIONS include:
|
|
[-a addr] is the I2C device address (hex). Default: 03 Current: 03
|
|
[-b bus] is the I2C bus number (decimal). Default: 0 Current: 0
|
|
[-r regaddr] is the I2C device register address (hex). Default: 00 Current: 00
|
|
[-w width] is the data width (8 or 16 decimal). Default: 8 Current: 8
|
|
[-s|n], send/don't send start between command and data. Default: -n Current: -n
|
|
[-i|j], Auto increment|don't increment regaddr on repititions. Default: NO Current: NO
|
|
[-f freq] I2C frequency. Default: 400000 Current: 400000
|
|
|
|
NOTES:
|
|
o An environment variable like $PATH may be used for any argument.
|
|
o Arguments are "sticky". For example, once the I2C address is
|
|
specified, that address will be re-used until it is changed.
|
|
|
|
WARNING:
|
|
o The I2C dev command may have bad side effects on your I2C devices.
|
|
Use only at your own risk.
|
|
nsh> i2c bus
|
|
BUS EXISTS?
|
|
Bus 0: YES
|
|
nsh> i2c dev 3 77
|
|
0 1 2 3 4 5 6 7 8 9 a b c d e f
|
|
00: -- -- -- -- -- -- -- -- -- -- -- -- --
|
|
10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
|
|
20: -- -- -- -- -- -- -- -- 28 -- -- -- -- -- -- --
|
|
30: -- -- -- -- -- -- -- 37 -- -- -- -- -- -- -- --
|
|
40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
|
|
50: -- -- -- -- -- -- -- 57 -- -- -- -- -- -- -- 5f
|
|
60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
|
|
70: -- -- -- -- -- -- -- --
|
|
|
|
Where 0x28 is the address of TWI interface to the EDBG and 0x57 and
|
|
0x5f are the addresses of the AT24 EEPROM (I am not sure what the
|
|
other address, 0x37, is as this writing).
|
|
|
|
6. TWIHS0 is also used to support 256 byte non-volatile storage for
|
|
configuration data using the MTD configuration as described above
|
|
under the heading, "MTD Configuration Data".
|
|
|
|
7. Support for HSMCI is built-in by default. The SAME70-XPLD provides
|
|
one full-size SD memory card slot. Refer to the section entitled
|
|
"SD card" for configuration-related information.
|
|
|
|
See "Open Issues" above for issues related to HSMCI.
|
|
|
|
The auto-mounter is not enabled. See the section above entitled
|
|
"Auto-Mounter".
|
|
|
|
8. Performance-related Configuration settings:
|
|
|
|
CONFIG_ARMV7M_ICACHE=y : Instruction cache is enabled
|
|
CONFIG_ARMV7M_DCACHE=y : Data cache is enabled
|
|
CONFIG_ARMV7M_DCACHE_WRITETHROUGH=n : Write back mode
|
|
CONFIG_ARCH_FPU=y : H/W floating point support is enabled
|
|
CONFIG_ARCH_DPFPU=y : 64-bit H/W floating point support is enabled
|
|
|
|
# CONFIG_ARMV7M_ITCM is not set : Support not yet in place
|
|
# CONFIG_ARMV7M_DTCM is not set : Support not yet in place
|
|
|
|
Stack sizes are also large to simplify the bring-up and should be
|
|
tuned for better memory usages.
|
|
|
|
STATUS:
|
|
2015-03-28: HSMCI TX DMA is disabled. There are some issues with the TX
|
|
DMA that need to be corrected.
|