Seeed Studio XIAO RA4M1

The Seeed Studio XIAO RA4M1 is a general purpose board supplied by Seeed Studio and it is compatible with the Renesas RA4M1 ecosystem, sharing the same MCU as Arduino R4 Minima (R7FA4M1AB3CFM).

../../../../../_images/xiao-ra4m1.jpg

Features

  • Renesas RA4M1, ARM® Dual Cortex-M4 @ 48MHz

  • 32kB SRAM, 256KkB Flash, 8KB EEPROM

  • Security: AES128/256

  • USB Type-C interface

  • 19 Pins:14x Analog,19x Digital, 2x IIC, 2x UART, 2x SPI

  • 1 user LED, 1 power LED,1 RGB LED (WS2812)

  • 1 RESET button, 1 BOOT button

Serial Console

By default, a serial console appears on pins 6 (TX GPIO) and pin 7 (RX GPIO). This console runs a 115200-8N1.

User LED

The USER LED, the yellow LED on the XIAO RA4M1, is connected to P011 according to the schematic diagram.

Buttons

The RESET and BOOT buttons can be used to enter “Renesas RA USB Boot” mode by reboot the board with BOOT shorted to GND and press the reset button twice (double click). The board will enumerate as “Renesas RA USB Boot”.

Pin Mapping

Pads numbered anticlockwise from USB connector.

Pad

Signal

Notes

0

P014

D0/A0

1

P000

D1/A1

2

P001

D2/A2

3

P002

D3/A3

4

P006

D4/SDA

5

P100

D5/SCL

6

P301

D6/Default TX for UART0 serial console

7

P301

D7/Default RX for UART0 serial console

8

P111

D8/SCK

9

P110

D9/MISO

10

P109

D10/MOSI

11

3V3

Power output to peripherals

12

Ground

13

VIN

+5V Supply to board

Power Supply

The working voltage of the MCU is 3.3V. Voltage input connected to general I/O pins may cause chip damage if it’s higher than 3.3V.

Installation

  1. Configure and build NuttX:

$ git clone https://github.com/apache/nuttx.git nuttx
$ git clone https://github.com/apache/nuttx-apps.git apps
$ cd nuttx
$ make distclean
$ ./tools/configure.sh xiao-ra4m1:nsh
$ make V=1

2. Connect the Seeed Studio XIAO RA4M1, and enter “Renesas RA USB Boot” mode, then, flash the nuttx.hex file using rfp-cli: (https://www.renesas.com/en/software-tool/renesas-flash-programmer-programming-gui)

Example command:

rfp-cli -device ra -port /dev/ttyACM0 -p ./build/nuttx.hex
  1. To access the console, TX and RX pins must be connected to the device such as USB-serial converter.

Configurations

nsh

Basic NuttShell configuration (console enabled in UART0, at 115200 bps).

combo

This configuration enabled NuttShell via Serial and enabled led and gpio examples:

Testing leds:

$nsh> leds
leds_main: Starting the led_daemon
leds_main: led_daemon started

led_daemon (pid# 5): Running
led_daemon: Opening /dev/userleds
led_daemon: Supported LEDs 0x01
led_daemon: LED set 0x01
$nsh> led_daemon: LED set 0x00
led_daemon: LED set 0x01
led_daemon: LED set 0x00
led_daemon: LED set 0x01
led_daemon: LED set 0x00
led_daemon: LED set 0x01

Testing gpios:

PIN/GPIO

Mode

Device

D0/P014

Input

/dev/gpio0

D1/P000

Output

/dev/gpio1

$nsh> gpio /dev/gpio0
Driver: /dev/gpio0
  Input pin:     Value=0
$nsh> gpio /dev/gpio0
Driver: /dev/gpio0
  Input pin:     Value=1