board: add M5Stamp C3

src/machine/board_m5stamp_c3.go

@@ -0,0 +1,49 @@
+//go:build m5stamp_c3
+// +build m5stamp_c3
+
+package machine
+
+const (
+	IO0  Pin = 0
+	IO1  Pin = 1
+	IO2  Pin = 2
+	IO3  Pin = 3
+	IO4  Pin = 4
+	IO5  Pin = 5
+	IO6  Pin = 6
+	IO7  Pin = 7
+	IO8  Pin = 8
+	IO9  Pin = 9
+	IO10 Pin = 10
+	IO11 Pin = 11
+	IO12 Pin = 12
+	IO13 Pin = 13
+	IO14 Pin = 14
+	IO15 Pin = 15
+	IO16 Pin = 16
+	IO17 Pin = 17
+	IO18 Pin = 18
+	IO19 Pin = 19
+	IO20 Pin = 20
+	IO21 Pin = 21
+
+	XTAL_32K_P = IO0
+	XTAL_32K_N = IO1
+	MTMS       = IO4
+	MTDI       = IO5
+	MTCK       = IO6
+	MTDO       = IO7
+	VDD_SPI    = IO11
+	SPIHD      = IO12
+	SPISP      = IO13
+	SPICS0     = IO14
+	SPICLK     = IO15
+	SPID       = IO16
+	SPIQ       = IO17
+	U0RXD      = IO20
+	U0TXD      = IO21
+)
+
+const (
+	WS2812 = IO2
+)