SAM E70 Xplained

Overview

The SAM E70 Xplained evaluation kit is a development platform to evaluate the Atmel SAM E70 series microcontrollers.

Hardware

  • ATSAME70Q21 ARM Cortex-M7 Processor
  • 12 MHz crystal oscillator
  • 32.768 kHz crystal oscillator (not populated)
  • AT24MAC402 EEPROM
  • IS42S16100E 16 Mb SDRAM
  • SD card connector
  • Ethernet port
  • Micro-AB USB device
  • Micro-AB USB debug interface supporting CMSIS-DAP, Virtual COM Port and Data Gateway Interface (DGI)
  • JTAG interface connector
  • One reset and one user pushbutton
  • One green user LED

Supported Features

The sam_e70_xplained board configuration supports the following hardware features:

Interface Controller Driver/Component
NVIC on-chip nested vector interrupt controller
SYSTICK on-chip systick
USART on-chip serial port
ETHERNET on-chip ethernet

Other hardware features are not currently supported by Zephyr.

The default configuration can be found in the Kconfig boards/arm/sam_e70_xplained/sam_e70_xplained_defconfig.

Connections and IOs

The SAME70-XPLD User Guide has detailed information about board connections.

System Clock

The SAM E70 MCU is configured to use the 12 MHz external oscillator on the board with the on-chip PLL to generate a 300 MHz system clock.

Serial Port

The ATSAME70Q21 MCU has five UARTs and three USARTs. One of the USARTs is configured for the console and is available as a Virtual COM Port via EDBG USB chip.

Programming and Debugging

Flashing

Flashing the Zephyr project onto SAM E70 MCU requires the OpenOCD tool. Support for Atmel SAM E microcontroller series was added in OpenOCD release 0.10.0. The current OpenOCD version available in the Zephyr SDK is 0.9 and unfortunately it does not support Atmel SAM E microcontrollers. Since few, if any major Linux distributions currently offer OpenOCD version 0.10.0 as a package you will have to compile and install it yourself. Make sure to enable CMSIS-DAP support as this is the debugging interface used by the on board EDBG chip.

By default SAM E70 chip will boot SAM-BA bootloader located in the ROM, not the flashed image. This can be changed with SAM Boot Assistant (SAM-BA) In-system Programmer from Atmel by reprogramming GPNVM1 (General-purpose NVM bit 1). This operation needs to be performed only once. If you do not need to debug your firmware you can also use SAM-BA instead of OpenOCD to flash your project.

  1. Build the Zephyr kernel and the application:

    $ cd $ZEPHYR_BASE/samples/hello_world/
$ make BOARD=sam_e70_xplained

  2. Connect the SAM E70 Xplained board to your host computer using the USB debug port.

  3. Run your favorite terminal program to listen for output. Under Linux the terminal should be /dev/ttyACM0. For example:

    $ minicom -D /dev/ttyACM0 -o

    The -o option tells minicom not to send the modem initialization string. Connection should be configured as follows:

    • Speed: 115200
    • Data: 8 bits
    • Parity: None
    • Stop bits: 1

  4. To flash the image, assuming the OpenOCD tool is already installed, enter:

    $ openocd -f board/atmel_same70_xplained.cfg -c "program outdir/sam_e70_xplained/zephyr.elf verify reset exit"

    The command will also verify that the image was programmed correctly, reset the board and run the Zephyr application.

    You should see “Hello World!” in your terminal.

Debugging

  1. Connect the SAM E70 Xplained board to your host computer using the USB debug port.

  2. Start GDB server on your host computer

    $ openocd -f board/atmel_same70_xplained.cfg&

  3. You can now use GDB remote debugging to connect to the target board. By default GDB server will listen on port 3333.