SenseBox MCU with SAMD21

Support for the SenseBox MCU with SAMD21 board.

General information

SenseBox is a do-it-yourself kit for stationary and mobile sensor stations.

SenseBox board is based on the Atmel SAMD21G18A microcontroller. See Atmel SAMD21.

Flash the board

  1. Put the board in bootloader mode by double tapping the reset button. When the board is in bootloader mode, the user led (red) oscillates smoothly.
  2. Use BOARD=sensebox_samd21 with the make command. Example with hello-world application: 
    1
    make BOARD=sensebox_samd21 -C examples/hello-world flash

Accessing STDIO via UART

To access the STDIO of RIOT, a FTDI to USB converted needs to be plugged to the UART/Serial 1 pins on the board.

On I2C port

I2C port is enabled by default. To disable it use I2C_DISABLE. To re-enable use I2C_ENABLE.

On XBEE ports

XBEE1 and XBEE2 ports are enabled by default. To disable any of them use XBEEn_DISABLE. To re-enable use XBEEn_ENABLE.

On the board there is a reset circuit for this ports that delays the reset signal from the enable signal for about 300ms. Because of that a delay has been introduced in the board_init function, so that any SPI device connected to the ports is reset before use.

SX127X radio

The pin configuration for the SX127X radio on the boards/sensebox_samd21/include/board.h** file assumes that it will be connected to the XBEE1 port. If a different configuraion is needed please modify this file.

SD card

The pin configuration for the mSD-Bee module radio on the boards/sensebox_samd21/include/sdcard_spi_params.h** file assumes that it will be connected to the XBEE2 port. If a different configuraion is needed please modify this file.

Limitations

There is only one interrupt pin on the XBEE headers. This means that interrupt pins DIO0 and DIO1 from the LoRa Bee are multiplexed through an OR gate.

This has the following limitations:

  • FSK mode is not possible
  • The interrupt pins can have different configurations, so caution is required when making changes.

SX127X radio

The pin configuration for the SX127X radio on the boards/sensebox_samd21/include/board.h** file assumes that it will be connected to the XBEE1 port. If a different configuraion is needed please modify this file.

SD card

The pin configuration for the mSD-Bee module radio on the boards/sensebox_samd21/include/sdcard_spi_params.h** file assumes that it will be connected to the XBEE2 port. If a different configuraion is needed please modify this file.

Limitations

There is only one interrupt pin on the XBEE headers. This means that interrupt pins DIO0 and DIO1 from the LoRa Bee are multiplexed through an OR gate.

This has the following limitations:

  • FSK mode is not possible
  • The interrupt pins can have different configurations, so caution is required when making changes.