targets: add support for Seeedstudio Xiao-RP2350 board.

Signed-off-by: deadprogram <ron@hybridgroup.com>

GNUmakefile

@@ -816,6 +816,8 @@ endif
 	@$(MD5SUM) test.hex
 	$(TINYGO) build -size short -o test.hex -target=vicharak_shrike-lite examples/echo
 	@$(MD5SUM) test.hex
+	$(TINYGO) build -size short -o test.hex -target=xiao-rp2350        examples/blinky1
+	@$(MD5SUM) test.hex
 	# test pwm
 	$(TINYGO) build -size short -o test.hex -target=itsybitsy-m0        examples/pwm
 	@$(MD5SUM) test.hex

src/machine/board_xiao-rp2350.go

@@ -0,0 +1,93 @@
+//go:build xiao_rp2350
+
+// This file contains the pin mappings for the Seeed XIAO RP2350 boards.
+//
+// XIAO RP2350 is a microcontroller using the Raspberry Pi RP2350 chip.
+//
+// - https://wiki.seeedstudio.com/XIAO-RP2350/
+package machine
+
+// Digital Pins
+const (
+	D0  Pin = GPIO26
+	D1  Pin = GPIO27
+	D2  Pin = GPIO28
+	D3  Pin = GPIO5
+	D4  Pin = GPIO6
+	D5  Pin = GPIO7
+	D6  Pin = GPIO0
+	D7  Pin = GPIO1
+	D8  Pin = GPIO2
+	D9  Pin = GPIO4
+	D10 Pin = GPIO3
+	D11 Pin = GPIO21
+	D12 Pin = GPIO20
+	D13 Pin = GPIO17
+	D14 Pin = GPIO16
+	D15 Pin = GPIO11
+	D16 Pin = GPIO12
+	D17 Pin = GPIO10
+)
+
+// Analog pins
+const (
+	A0 Pin = D0
+	A1 Pin = D1
+	A2 Pin = D2
+)
+
+// Onboard LEDs
+const (
+	NEOPIXEL       = GPIO22
+	WS2812         = GPIO22
+	NEO_PWR        = GPIO23
+	NEOPIXEL_POWER = GPIO23
+
+	LED = GPIO25
+)
+
+// I2C pins
+const (
+	I2C0_SDA_PIN Pin = D14
+	I2C0_SCL_PIN Pin = D13
+
+	I2C1_SDA_PIN Pin = D4
+	I2C1_SCL_PIN Pin = D5
+)
+
+// SPI pins
+const (
+	SPI0_SCK_PIN Pin = D8
+	SPI0_SDO_PIN Pin = D10
+	SPI0_SDI_PIN Pin = D9
+
+	SPI1_SCK_PIN Pin = D17
+	SPI1_SDO_PIN Pin = D15
+	SPI1_SDI_PIN Pin = D16
+)
+
+// Onboard crystal oscillator frequency, in MHz.
+const (
+	xoscFreq = 12 // MHz
+)
+
+// UART pins
+const (
+	UART0_TX_PIN = GPIO0
+	UART0_RX_PIN = GPIO1
+	UART_TX_PIN  = UART0_TX_PIN
+	UART_RX_PIN  = UART0_RX_PIN
+)
+
+var DefaultUART = UART0
+
+// USB CDC identifiers
+const (
+	usb_STRING_PRODUCT      = "XIAO RP2350"
+	usb_STRING_MANUFACTURER = "Seeed"
+)
+
+var (
+	usb_VID uint16 = 0x2e8a
+	usb_PID uint16 = 0x000a
+)

targets/xiao-rp2350.json

@@ -0,0 +1,8 @@
+{
+    "inherits": [
+        "rp2350"
+    ],
+    "serial-port": ["2e8a:000a"],
+    "build-tags": ["xiao_rp2350"],
+    "default-stack-size": 8192
+}