README ====== This README file discusses the port of NuttX to the Atmel SAM V71 Xplained Ultra Evaluation Kit (SAMV71-XULT). This board features the ATSAMV71Q21 Cortex-M7 microcontroller. Contents ======== - Board Features - Serial Console - LEDs and Buttons - Configurations Board Features ============== - ATSAMV71Q21 microcontroller: Cortex-M7, 300MHz, 2MiB FLASH, 384KiB SRAM, I/D-caches - One mechanical reset button - One power switch button - Two mechanical user pushbuttons - Two yellow user LEDs - Supercap backup - 12.0 MHz crystal - 32.768 kHz crystal - 2 MB SDRAM - 2 MB QSPI Flash - IEEE 802.3az 10Base-T/100Base-TX Ethernet RMII PHY - AT24MAC402 256KByte EEPROM with EUI-48 address - WM8904 stereo audio codec - ATA6561 CAN Transceiver - SD Card connector with SDIO support - Camera interface connector - MediaLB connector - Two Xplained Pro extension headers - One Xplained Pro LCD header - Coresight 20 connector for 4-bit ETM - Arduino due compatible shield connectors - External debugger connector - USB interface, device and host mode - Embedded Debugger with Data Gateway Interface and Virtual COM port (CDC) - External power input (5-14V) or USB powered See the Atmel webite for further information about this board: - http://www.atmel.com/tools/atsamv71-xult.aspx Serial Console ============== The SAMV71-XULT has no on-board RS-232 drivers so it will be necessary to use either the VCOM or an external RS-232 driver. Here are some options. - Arduino Serial Shield: One option is to use an Arduino-compatible serial shield. This will use the RXD and TXD signals available at pins 0 an 1, respectively, of the Arduino "Digital Low" connector. On the SAMV71-XULT board, this corresponds to UART3: ------ ------ ------- ------- -------- Pin on SAMV71 Arduino Arduino SAMV71 J503 PIO Name Pin Function ------ ------ ------- ------- -------- 1 PD28 RX0 0 URXD3 2 PD30 TX0 1 UTXD3 ------ ------ ------- ------- -------- - SAMV7-XULT EXTn connectors. USART pins are also available the EXTn connectors. The following are labelled in the User Guide for USART functionality: ---- -------- ------ -------- EXT1 EXTI1 SAMV71 SAMV71 Pin Name PIO Function ---- -------- ------ -------- 13 USART_RX PB00 RXD0 14 USART_TX PB01 TXD0 ---- -------- ------ -------- EXT2 EXTI2 SAMV71 SAMV71 Pin Name PIO Function ---- -------- ------ -------- 13 USART_RX PA21 RXD1 14 USART_TX PB04 TXD1 - VCOM. The Virtual Com Port gateway is available on USART1: ------ -------- SAMV71 SAMV71 PIO Function ------ -------- PB04 TXD1 PA21 RXD1 ------ -------- Any of these options can be selected as the serial console by: 1. Enabling the UART/USART peripheral in the "System Type -> Peripheral Selection" menu, then 2. Configuring the peripheral in the "Drivers -> Serial Configuration" menu. LEDs and Buttons ================ LEDs ---- There are two yellow LED available on the SAM V71 Xplained Ultra board that can be turned on and off. The LEDs can be activated by driving the connected I/O line to GND. ------ ----------- --------------------- SAMV71 Function Shared functionality PIO ------ ----------- --------------------- PA23 Yellow LED0 EDBG GPIO PC09 Yellow LED1 LCD, and Shield ------ ----------- --------------------- These LEDs are not used by the board port 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 LED0 LED1 ------------------- ----------------------- -------- -------- LED_STARTED NuttX has been started OFF OFF LED_HEAPALLOCATE Heap has been allocated OFF OFF LED_IRQSENABLED Interrupts enabled OFF OFF LED_STACKCREATED Idle stack created ON OFF LED_INIRQ In an interrupt No change LED_SIGNAL In a signal handler No change LED_ASSERTION An assertion failed No change LED_PANIC The system has crashed N/C Blinking LED_IDLE MCU is is sleep mode Not used ------------------- ----------------------- -------- -------- Thus if LED0 is statically on, NuttX has successfully booted and is, apparently, running normally. If LED1 is flashing at approximately 2Hz, then a fatal error has been detected and the system has halted. NOTE: That LED0 is not used after completion of booting and may be used by other board-specific logic. Buttons ------- SAM V71 Xplained Ultra contains three mechanical buttons. One button is the RESET button connected to the SAM V71 reset line and the others are generic user configurable buttons. When a button is pressed it will drive the I/O line to GND. ------ ----------- --------------------- SAMV71 Function Shared functionality PIO ------ ----------- --------------------- RESET RESET Trace, Shield, and EDBG PA09 SW0 EDBG GPIO and Camera PB12 SW1 EDBG SWD and Chip Erase ------ ----------- --------------------- NOTES: - There are no pull-up resistors connected to the generic user buttons so it is necessary to enable the internal pull-up in the SAM V71 to use the button. - PB12 is set up as a system flash ERASE pin when the firmware boots. To use the SW1, PB12 has to be configured as a normal regular I/O pin in the MATRIX module. For more information see the SAM V71 datasheet. Configurations ==============