| .. _adafruit_grand_central_m4_express: |
| |
| Adafruit Grand Central M4 Express |
| ################################# |
| |
| Overview |
| ******** |
| |
| The Adafruit Grand Central M4 Express is an ARM development board with the |
| form factor of an Arduino Mega. |
| It features 70 GPIO pins, a microSDHC slot and 8MiB of QSPI Flash. |
| |
| .. figure:: img/adafruit_grand_central_m4_express.webp |
| :width: 800px |
| :align: center |
| :alt: Adafruit Grand Central M4 Express |
| |
| Adafruit Grand Central M4 Express (Credit: Kattni Rembor / Adafruit) |
| |
| Hardware |
| ******** |
| |
| - ATSAMD51P20A ARM Cortex-M4F processor at 120 MHz |
| - 1024 KiB of flash memory and 256 KiB of RAM |
| - 8 MiB of QSPI flash |
| - A red user LED |
| - A RGB "NeoPixel" / WS2812B LED |
| - A microSDHC slot (connected via SPI) |
| - Native USB port |
| |
| Supported Features |
| ================== |
| |
| The adafruit_grand_central_m4_express board configuration supports the following |
| hardware features: |
| |
| +-----------+------------+------------------------------------------+ |
| | Interface | Controller | Driver/Component | |
| +===========+============+==========================================+ |
| | NVIC | on-chip | Nested vector interrupt controller | |
| +-----------+------------+------------------------------------------+ |
| | SYSTICK | on-chip | SysTick | |
| +-----------+------------+------------------------------------------+ |
| | WDT | on-chip | Watchdog | |
| +-----------+------------+------------------------------------------+ |
| | GPIO | on-chip | I/O ports, User LED | |
| +-----------+------------+------------------------------------------+ |
| | UART | on-chip | Serial ports, Console | |
| +-----------+------------+------------------------------------------+ |
| | SPI | on-chip | SPI ports, microSDHC slot | |
| +-----------+------------+------------------------------------------+ |
| | TRNG | on-chip | True Random Number Generator | |
| +-----------+------------+------------------------------------------+ |
| | RTC | on-chip | Real-Time Counter | |
| +-----------+------------+------------------------------------------+ |
| | USB | on-chip | USB device | |
| +-----------+------------+------------------------------------------+ |
| | WDT | on-chip | Watchdog Timer | |
| +-----------+------------+------------------------------------------+ |
| |
| Other hardware features are not currently supported by Zephyr. |
| |
| The default configuration can be found in the Kconfig file |
| :zephyr_file:`boards/arm/adafruit_grand_central_m4_express/adafruit_grand_central_m4_express_defconfig`. |
| |
| Connections and IOs |
| =================== |
| |
| The `Adafruit Learning System`_ has detailed information about |
| the board including `pinouts`_ and the `schematics`_. |
| |
| System Clock |
| ============ |
| |
| The SAMD51 MCU is configured to use the 32.768 kHz external oscillator |
| with the on-chip PLL generating the 120 MHz system clock. |
| |
| Serial Port |
| =========== |
| |
| The SAMD51 MCU has 8 SERCOM based UARTs. On the Grand Central, SERCOM0 is |
| the Zephyr console and is available on RX(PB25) and TX(PB24). |
| |
| SPI Port |
| ======== |
| |
| The SAMD51 MCU has 8 SERCOM based SPIs. On the Grand Central, SERCOM7 has been |
| set into SPI mode to connect to devices over the SCK(PD09), MOSI(PD08), and MISO(PD11) pins. |
| Additionally SERCOM2 has been configured as SPI to access the microSDHC card. |
| |
| I2C Port |
| ======== |
| |
| The SAMD51 MCU has 8 SERCOM based I2Cs. On the Grand Central, SERCOM3 has been |
| configured as I2C to connect to devices over the SCL(PB21) and SDA(PB20) pins. |
| |
| USB Device Port |
| =============== |
| |
| The SAMD51 MCU has a USB device port that can be used to communicate |
| with a host PC. See the :ref:`usb-samples` sample applications for |
| more, such as the :zephyr:code-sample:`usb-cdc-acm` sample which sets up a virtual |
| serial port that echos characters back to the host PC. |
| |
| Programming and Debugging |
| ************************* |
| |
| The Grand Central ships with a BOSSA compatible UF2 bootloader. |
| The bootloader can be entered by quickly tapping the reset button twice. |
| |
| Flashing |
| ======== |
| |
| #. Build the Zephyr kernel and the :ref:`hello_world` sample application: |
| |
| .. zephyr-app-commands:: |
| :zephyr-app: samples/hello_world |
| :board: adafruit_grand_central_m4_express |
| :goals: build |
| :compact: |
| |
| #. Connect the Grand Central to your host computer using USB. |
| |
| #. Connect a 3.3 V USB to serial adapter to the board and to the |
| host. See the `Serial Port`_ section above for the board's pin |
| connections. |
| |
| #. Run your favorite terminal program to listen for output. Under Linux the |
| terminal should be :code:`/dev/ttyUSB0`. For example: |
| |
| .. code-block:: console |
| |
| $ minicom -D /dev/ttyUSB0 -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 |
| |
| #. Tap the reset button twice quickly to enter bootloader mode |
| |
| #. Flash the image: |
| |
| .. zephyr-app-commands:: |
| :zephyr-app: samples/hello_world |
| :board: adafruit_grand_central_m4_express |
| :goals: flash |
| :compact: |
| |
| You should see "Hello World! adafruit_grand_central_m4_express" in your terminal. |
| |
| Debugging |
| ========= |
| |
| In addition to the built-in bootloader, the Grand Central can be flashed and |
| debugged using a SWD probe such as the Segger J-Link. |
| |
| #. Connect the probe to the board using the 10-pin SWD interface. |
| |
| #. Flash the image: |
| |
| .. zephyr-app-commands:: |
| :zephyr-app: samples/hello_world |
| :board: adafruit_grand_central_m4_express |
| :goals: flash |
| :flash-args: -r openocd |
| :compact: |
| |
| #. Start debugging: |
| |
| .. zephyr-app-commands:: |
| :zephyr-app: samples/hello_world |
| :board: adafruit_grand_central_m4_express |
| :goals: debug |
| :compact: |
| |
| References |
| ********** |
| |
| .. target-notes:: |
| |
| .. _Adafruit Learning System: |
| https://learn.adafruit.com/adafruit-grand-central |
| |
| .. _pinouts: |
| https://learn.adafruit.com/adafruit-grand-central/pinouts |
| |
| .. _schematics: |
| https://learn.adafruit.com/adafruit-grand-central/downloads |
| |
| .. _J-Link: |
| https://www.segger.com/products/debug-probes/j-link/technology/interface-description/ |