README
======
This README discusses issues unique to NuttX configurations for the
Mikroe Flip&Click SAM3X board. This board is an Arduino-Due work-alike
with four Mikroe Click bus interfaces. Like the Arduino-Due, this board
features the Atmel ATSAM3X8E MCU running at 84 MHz.
Thanks to John Legg for contributing the Flip&Click SAM3X board!
Contents
========
- STATUS
- Buttons and LEDs
- Serial Consoles
- SPI
- I2C
- SSD1306 OLED
- Loading Code
- Flip&Click SAM3X-specific Configuration Options
- Configurations
STATUS
======
2018-01-07: Created the configuration. At present it does not work; I
believe because of tool-related issues. See discussion under "Loading
Code" below.
2018-01-24: I ordered a JTAG connector and soldered that to the Flip'n'Click
and I am now successfully able to load code. The NSH configuration appears
to be fully functional.
2018-02-11: Added the nxlines configuration to test the custom HiletGo
OLED on a Click proto board. This is the same logic from the Flip&Click
PIC32MZ and the result is the same: No complaints from the software, but
nothing appears on the OLED. There is, most likely, an error in my custom
HiletGo Click. Damn!
Buttons and LEDs
================
Buttons
-------
There are no buttons on the Flip&Click SAM3X board.
LEDs
----
There are four LEDs on the top, blue side of the board. Only
one can be controlled by software:
LED L - PB27 (PWM13)
There are also four LEDs on the back, white side of the board:
LED A - PC6
LED B - PC5
LED C - PC7
LED D - PC8
A high output value illuminates the LEDs.
These LEDs are available to the application and are all available to the
application unless CONFIG_ARCH_LEDS is defined. In that case, the usage
by the board port is defined in include/board.h and src/sam_autoleds.c.
The LEDs are used to encode OS-related events as follows:
SYMBOL MEANING LED STATE
L A B C D
---------------- ----------------------- --- --- --- --- ---
LED_STARTED NuttX has been started OFF ON OFF OFF OFF
LED_HEAPALLOCATE Heap has been allocated OFF OFF ON OFF OFF
LED_IRQSENABLED Interrupts enabled OFF OFF OFF ON OFF
LED_STACKCREATED Idle stack created OFF OFF OFF OFF ON
LED_INIRQ In an interrupt GLO N/C N/C N/C N/C
LED_SIGNAL In a signal handler GLO N/C N/C N/C N/C
LED_ASSERTION An assertion failed GLO N/C N/C N/C N/C
LED_PANIC The system has crashed 2Hz N/C N/C N/C N/C
LED_IDLE MCU is is sleep mode ---- Not used -----
Thus if LED L is glowing faintly and all other LEDs are off (except LED D
which was left on but is no longer controlled by NuttX and so may be in any
state), NuttX has successfully booted and is, apparently, running normally
and taking interrupts. If any of LEDs A-D are statically set, then NuttX
failed to boot and the LED indicates the initialization phase where the
failure occurred. If LED L is flashing at approximately 2Hz, then a fatal
error has been detected and the system has halted.
NOTE: After booting, LEDs A-D are no longer used by the system and may
be controlled the application.
Serial Consoles
===============
The SAM3X has a UART and 4 USARTS. The Programming port uses a USB-to-
serial chip connected to the first of the MCU (RX0 and TX0 on PA8 and PA9,
respectively). The output from that port is visible using the Arduino tool.
[NOTE: My experience so far: I get serial output on the virtual COM port
via the UART, but I receive no serial input for keyboard data entered in
the PC serial terminal. I have not investigated this problem. It may
be something as simple as the Rx pin configuration. Instead, I just
switched to USART0.]
Other convenient U[S]ARTs that may be used as the Serial console include:
1) An Arduino Serial Shield. The RX and TX pins are available on the
Arduino connector D0 and D1 pins, respectively. These are connected
to USART0, RXD0 and TXD0 which are PA10 and PA11, respectively.
2) Mikroe Click Serial Shield. There are four Click bus connectors with
serial ports available as follows:
Click A: USART0 RXD0 and TXD0 which are, again, PA10 and PA11.
Click B: USART1 RXD1 and TXD1 which are PA12 and PA13, respectively.
Click C: USART3 RXD3 and TXD3 which are PD5 and PD4, respectively.
Click D: USART3 RXD3 and TXD3 which are, again, PD5 and PD4.
Other serial ports are probably available on the Arduino connector. I
will leave that as an exercise for the interested reader.
The outputs from these pins is 3.3V. You will need to connect RS232
transceiver to get the signals to RS232 levels (or connect to the
USB virtual COM port in the case of UART0).
Any of UART and USART0-3 may be used as a serial console. UART0 would
be the preferred default console setting. However, due to the communication
problems mentioned above, USART0 is used as the default serial console
in all configurations. But that is easily changed by modifying the
configuration as described under "Configurations" below.
SPI
===
SPI0 is available on the Arduino compatible SPI connector (but no SPI is
available on pins D10-D13 of the main Arduino Shield connectors where
you might expect then). The SPI connector is configured as follows:
Pin Board Signal SAM3X Pin Board Signal SAM3X
--- ------------ ----- --- ------------ -----
1 SPI0_MISO PA25 2 VCC-5V N/A
3 SPI0_SCK PA27 4 SPI0_MOSI PA26
5 MRST NRSTB 6 GND N/A
SPI0 is also available on each of the mikroBUS Click connectors (in
addition to 5V and GND). The connectivity differs only in the chip
select pin:
MikroBUS A: MikroBUS B:
Pin Board Signal SAM3X Pin Board Signal SAM3X
---- ------------ ----- ---- ------------ -----
CS SPI0_CS0 PA28 CS PA29 PA29
SCK SPI0_SCK PA27 SCK SPI0_SCK PA27
MISO SPI0_MISO PA25 MISO SPI0_MISO PA25
MOSI SPI0_MOSI PA26 MOSI SPI0_MOSI PA26
MikroBUS C: MikroBUS D:
Pin Board Signal SAM3X Pin Board Signal SAM3X
---- ------------ ----- ---- ------------ -----
CS SPI0_CS2 PB21 CS SPI0_CS3 PB23
SCK SPI0_SCK PA27 SCK SPI0_SCK PA27
MISO SPI0_MISO PA25 MISO SPI0_MISO PA25
MOSI SPI0_MOSI PA26 MOSI SPI0_MOSI PA26
I2C
===
I2C0 is available on pins D16-D17 of the Arduino Shield connectors where
you would expect then. The SPI connector is configured as follows:
Pin Label J1 Board Signal SAM3X
--- ----- -- ------------ -----
D16 SCL1 8 I2C0_SCL PA17
D17 SDA1 7 I2C0_SDA PA18
I2C0 and I2C1 are also available on the mikroBUS Click connectors (in
addition to 5V and GND). The connectors A and B share I2C0 with the
Arduino shield connector. Connectors C and D both connect to I2C1:
MikroBUS A: MikroBUS B:
Pin Board Signal SAM3X Pin Board Signal SAM3X
---- ------------ ----- ---- ------------ -------
SCL I2C0_SCL PA17 SCL I2C0_SCL PA17
SDA I2C0_SDA PA1 SDA I2C0_SDA PA18
MikroBUS C: MikroBUS D:
Pin Board Signal SAM3X Pin Board Signal SAM3X
---- ------------ ----- ---- ------------ -------
SCL I2C1_SCL PB13 SCL I2C1_SCL PB13
SDA I2C1_SDA PB12 SDA I2C1_SDA PB12
SSD1306 OLED
============
Hardware
--------
The HiletGo is a 128x64 OLED that can be driven either via SPI or I2C (SPI
is the default and is what is used here). I have mounted the OLED on a
proto click board. The OLED is connected as follows:
OLED ALIAS DESCRIPTION PROTO CLICK
----- ----------- ------------- -----------------
GND Ground GND
VCC Power Supply 5V (3-5V)
D0 SCL,CLK,SCK Clock SCK
D1 SDA,MOSI Data MOSI,SDI
RES RST,RESET Reset RST (GPIO OUTPUT)
DC AO Data/Command INT (GPIO OUTPUT)
CS Chip Select CS (GPIO OUTPUT)
NOTE that this is a write-only display (MOSI only)!
Loading Code
============
[NOTE: This text was mostly copied from the Arduino Due README.txt. I
believe, however, that there have been significant changes to the
tool environment such that Bossac may no longer be usable. I don't
know that for certain and perhaps someone with more knowledge of
the tools than I could make this work. See STATUS below for the
current issues that I see.]
Installing the Arduino USB Driver under Windows
-----------------------------------------------
1. Download the Windows version of the Arduino software, not the 1.0.x
release but the latest (1.5.x or later) that supports the Arduino
Due. When the download finishes, unzip the downloaded file.
In the current 1.8.x release, the Arduino Due support is not included
in the base package but can be added by selecting the "Boards Manager"
from the "Tools" menu.
2. Connect the Flip&Click to your computer with a USB cable via the
Programming port.
3. The Windows driver installation should fail.
4. Open the Device Manager
5. Look for the listing named "Ports (COM & LPT)". You should see an open
port named "Arduino Due Prog. Port". Right click and select "Update
driver".
6. Select the "Browse my computer for Driver software" option.
7. Right click on the "Arduino Due Prog. Port" and choose "Update Driver
Software".
8. Navigate to the folder with the Arduino IDE you downloaded and unzipped
earlier. Locate and select the "Drivers" folder in the main Arduino
folder (not the "FTDI USB Drivers" sub-directory).
Loading NuttX to the Flip&Click Using Bossa
-------------------------------------------
Arduino uses BOSSA under the hood to load code and you can use BOSSA
outside of Arduino.
Where do you get it?
Generic BOSSA installation files are available here:
https://github.com/shumatech/BOSSA (formerly at
http://sourceforge.net/projects/b-o-s-s-a/?source=dlp)
Pre-built binaries are available: https://github.com/shumatech/BOSSA/releases
The original Arduino DUE used a patched version of BOSSA available
as source code here: https://github.com/shumatech/BOSSA/tree/arduino
But that has most likely been incorporated into the main github
repository.
But, fortunately, since you already installed Arduino, you already have
BOSSA installed. In my installation, it is here:
C:\Program Files (x86)\Arduino\arduino-1.5.2\hardware\tools\bossac.exe
General Procedure
1) Erase the FLASH and put the Flip&Click in bootloader mode
2) Write the file to FLASH
3) Configure to boot from FLASH
4) Reset the Flip&Click
Erase FLASH and Put the Flip&Click in Bootloader Mode
This is accomplished by simply configuring the programming port in 1200
baud and sending something on the programming port. Here is some sample
output from a Windows CMD.exe shell. NOTE that my Arduino programming
port shows up as COM7. It may be different on your system.
To enter boot mode, set the baud to 1200 and send anything to the
programming port:
C:\Program Files (x86)\Arduino\arduino-1.5.2\hardware\tools>mode com26:1200,n,8,1
Status for device COM7:
------------------------
Baud: 1200
Parity: None
Data Bits: 8
Stop Bits: 1
Timeout: ON
XON/XOFF: OFF
CTS handshaking: OFF
DSR handshaking: OFF
DSR sensitivity: OFF
DTR circuit: ON
RTS circuit: ON
C:\Program Files (x86)\Arduino\arduino-1.5.2\hardware\tools>bossac.exe --port=COM7 --usb-port=false -i
Device : ATSAM3X8
Version : v1.1 Dec 15 2010 19:25:04
Address : 0x80000
Pages : 2048
Page Size : 256 bytes
Total Size : 512KB
Planes : 2
Lock Regions : 32
Locked : none
Security : false
Boot Flash : false
Writing FLASH and Setting FLASH Boot Mode
In a Cygwin BaSH shell:
export PATH="/cygdrive/c/Program Files (x86)/Arduino/arduino-1.5.2/hardware/tools":$PATH
Erasing, writing, and verifying FLASH with bossac:
$ bossac.exe --port=COM7 --usb-port=false -e -w -v -b nuttx.bin -R
Erase flash
Write 86588 bytes to flash
[==============================] 100% (339/339 pages)
Verify 86588 bytes of flash
[==============================] 100% (339/339 pages)
Verify successful
Set boot flash true
CPU reset.
Some things that can go wrong:
$ bossac.exe --port=COM7 --usb-port=false -e -w -v -b nuttx.bin -R
No device found on COM7
This error means that there is code running on the Flip&Click already
so the bootloader cannot connect. Press reset and try again
$ bossac.exe --port=COM7 --usb-port=false -e -w -v -b nuttx.bin -R
No device found on COM7
Sill No connection because the board does not jump to bootloader after
reset. Set the baud to 1200 and send something then try again
$ bossac.exe --port=COM7 --usb-port=false -e -w -v -b nuttx.bin -R
Erase flash
Write 86588 bytes to flash
[==============================] 100% (339/339 pages)
Verify 86588 bytes of flash
[==============================] 100% (339/339 pages)
Verify successful
Set boot flash true
CPU reset.
Other useful bossac operations.
a) Write code to FLASH don't change boot mode and don't reset. This lets
you examine the FLASH contents that you just loaded while the bootloader
is still active.
$ bossac.exe --port=COM7 --usb-port=false -e -w -v --boot=0 nuttx.bin
Write 64628 bytes to flash
[==============================] 100% (253/253 pages)
Verify 64628 bytes of flash
[==============================] 100% (253/253 pages)
Verify successful
b) Verify the FLASH contents (the bootloader must be running)
$ bossac.exe --port=COM7 --usb-port=false -v nuttx.bin
Verify 64628 bytes of flash
[==============================] 100% (253/253 pages)
Verify successful
c) Read from FLASH to a file (the bootloader must be running):
$ bossac.exe --port=COM7 --usb-port=false --read=4096 nuttx.dump
Read 4096 bytes from flash
[==============================] 100% (16/16 pages)
d) Change to boot from FLASH
$ bossac.exe --port=COM7 --usb-port=false --boot=1
Set boot flash true
STATUS:
At present this procedure does not work. I do the following:
a) Open TeraTerm, select COM7 at 1200 baud, type a few ENTERs, and
close teraterm.
b) Execute the following command which claims to have successfully
written to FLASH.
bossac.exe --info --debug --port COM7 --usb-port=0 --erase --write --verify -b nuttx.bin -R
But the code does not boot. There is no indication of life.
c) Repeat a) then
bossac.exe --info --debug --port COM7 --usb-port=0 --verify -b nuttx.bin
And it says that the content of the FLASH is not good.
Uploading NuttX to the Flip&Click Using JTAG
--------------------------------------------
The JTAG/SWD signals are brought out to a 10-pin header JTAG connector:
PIN SIGNAL JTAG STANDARD NOTES
--- -------------- ----------------- --------------------------------
1 VCC-3.3V VTref
2 JTAG_TMS SWDIO/TMS SAM3X pin 31, Pulled up on board
3 GND GND
4 JTAG_TCK SWDCLK/TCK SAM3X pin 28, Pulled up on board
5 GND GND
6 JTAG_TDO SWO/EXta/TRACECTL SAM3X pin 30, Pulled up on board
7 N/C Key
8 JTAG_TDI NC/EXTb/TDI SAM3X pin 29, Pulled up on board
9 GND GNDDetect
10 MRST nReset
NOTE: The 10-pin JTAG connector is not populated on the Flip&Click
SAM3X. This is the part number for the SMD connector recommended by
ARM.com: Samtec FTSH-105-01-L-DV-K. For example:
https://www.digikey.com/product-detail/en/samtec-inc/FTSH-105-01-L-DV-K/SAM8799-ND/1875039
You should be able to use a 10- to 20-pin adapter to connect a SAM-ICE
or J-Link debugger to the Flip&Click SAM3X. I have this Olimex adapter:
https://www.olimex.com/Products/ARM/JTAG/ARM-JTAG-20-10/ . I have been
loading code and debugging with no problems using JTAG.
Flip&Click SAM3X-specific Configuration Options
===============================================
CONFIG_ARCH - Identifies the arch/ subdirectory. This should
be set to:
CONFIG_ARCH=arm
CONFIG_ARCH_family - For use in C code:
CONFIG_ARCH_ARM=y
CONFIG_ARCH_architecture - For use in C code:
CONFIG_ARCH_CORTEXM3=y
CONFIG_ARCH_CHIP - Identifies the arch/*/chip subdirectory
CONFIG_ARCH_CHIP="sam34"
CONFIG_ARCH_CHIP_name - For use in C code to identify the exact
chip:
CONFIG_ARCH_CHIP_SAM34
CONFIG_ARCH_CHIP_SAM3X
CONFIG_ARCH_CHIP_ATSAM3X8E
CONFIG_ARCH_BOARD - Identifies the boards/ subdirectory and
hence, the board that supports the particular chip or SoC.
CONFIG_ARCH_BOARD=flipnclick-sam3x (for the Flip&Click SAM3X development board)
CONFIG_ARCH_BOARD_name - For use in C code
CONFIG_ARCH_BOARD_FLIPNCLICK_SAM3X=y
CONFIG_ARCH_LOOPSPERMSEC - Must be calibrated for correct operation
of delay loops
CONFIG_RAM_SIZE - Describes the installed DRAM (SRAM in this case):
CONFIG_RAM_SIZE=65536 (64Kb)
CONFIG_RAM_START - The start address of installed DRAM
CONFIG_RAM_START=0x20000000
CONFIG_ARCH_LEDS - Use LEDs to show state. Unique to boards that
have LEDs
Individual subsystems can be enabled:
CONFIG_SAM34_ADC12B - 12-bit Analog To Digital Converter
CONFIG_SAM34_CAN0 - CAN Controller 0
CONFIG_SAM34_CAN1 - CAN Controller 1
CONFIG_SAM34_DACC - Digital To Analog Converter
CONFIG_SAM34_DMAC0 - DMA Controller
CONFIG_SAM34_EMAC - Ethernet MAC
CONFIG_SAM34_HSMCI - High Speed Multimedia Card Interface
CONFIG_SAM34_PWM - Pulse Width Modulation
CONFIG_SAM34_RTC - Real Time Clock
CONFIG_SAM34_RTT - Real Time Timer
CONFIG_SAM34_SDRAMC - SDRAM Controller
CONFIG_SAM34_SMC - Static Memory Controller
CONFIG_SAM34_SPI0 - Serial Peripheral Interface 0
CONFIG_SAM34_SPI1 - Serial Peripheral Interface 1
CONFIG_SAM34_SSC - Synchronous Serial Controller
CONFIG_SAM34_TC0 - Timer Counter 0
CONFIG_SAM34_TC1 - Timer Counter 1
CONFIG_SAM34_TC2 - Timer Counter 2
CONFIG_SAM34_TC3 - Timer Counter 3
CONFIG_SAM34_TC4 - Timer Counter 4
CONFIG_SAM34_TC5 - Timer Counter 5
CONFIG_SAM34_TC6 - Timer Counter 6
CONFIG_SAM34_TC7 - Timer Counter 7
CONFIG_SAM34_TC8 - Timer Counter 8
CONFIG_SAM34_TRNG - True Random Number Generator
CONFIG_SAM34_TWIM/S0 - Two-Wire Interface 0 (master/slave)
CONFIG_SAM34_TWIM/S1 - Two-Wire Interface 1 (master/slave)
CONFIG_SAM34_UART0 - UART 0
CONFIG_SAM34_UOTGHS - USB OTG High Speed
CONFIG_SAM34_USART0 - USART 0
CONFIG_SAM34_USART1 - USART 1
CONFIG_SAM34_USART2 - USART 2
CONFIG_SAM34_USART3 - USART 3
CONFIG_SAM34_WDT - Watchdog Timer
Some subsystems can be configured to operate in different ways. The drivers
need to know how to configure the subsystem.
CONFIG_SAM34_GPIOA_IRQ
CONFIG_SAM34_GPIOB_IRQ
CONFIG_SAM34_GPIOC_IRQ
CONFIG_SAM34_GPIOD_IRQ
CONFIG_SAM34_GPIOE_IRQ
CONFIG_SAM34_GPIOF_IRQ
Configurations
==============
Each Flip&Click SAM3X configuration is maintained in a sub-directory and
can be selected as follow:
tools/configure.sh [OPTIONS] flipnclick-sam3x:<subdir>
Where typical options are -l to configure to build on Linux or -c to
configure for Cygwin under Linux. 'tools/configure.sh -h' will show
you all of the options.
Before building, make sure the PATH environment variable includes 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
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 USART0 which is available either on the Arduion Shield
connector or on mikroBUS A as described above in the section entitled
"Serial Consoles".
3. Unless otherwise stated, the configurations are setup for
Cygwin under Windows:
Build Setup:
CONFIG_HOST_WINDOWS=y : Microsoft Windows
CONFIG_WINDIWS_CYGWIN=y : Cygwin under Windows
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:
System Type -> Toolchain:
CONFIG_ARMV7M_TOOLCHAIN_GNU_EABI=y : GNU ARM EABI toolchain for Windows
Configuration sub-directories
-----------------------------
nsh:
This configuration directory will build the NuttShell. See NOTES above.
NOTES:
1. NSH built-in applications are supported. However, there are
no built-in applications built with the default configuration.
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
nxlines
This is an NSH configuration that supports the NX graphics example at
apps/examples/nxlines as a built-in application.
NOTES:
1. This configuration derives from the nsh configuration. All of the
notes there apply here as well.
2. The default configuration assumes there is the custom HiletGo OLED
in the mikroBUS B slot (and a Mikroe RS-232 Click card in the
mikroBUS A slot). That is easily changed by reconfiguring, however.
See the section entitled "HiletGo OLED" for information about this
custom click card.
STATUS:
2018-02-11: No complaints from the software, but nothing appears on the
OLED. There is, most likely, an error in my custom HiletGo Click. Damn!
