i2csoft: add support for software I2C

2026-08-21 06:59:00 +00:00 · 2021-09-22 23:31:02 +09:00
parent 94729a4f7d
commit bd42656644
7 changed files with 396 additions and 1 deletions
@@ -0,0 +1,23 @@
+//go:build atsamd51 || atsame5x
+// +build atsamd51 atsame5x
+
+package i2csoft
+
+import (
+	"device/arm"
+)
+
+func (i2c *I2C) wait() {
+	// atsamd51
+	//  1 : about 388kHz
+	// 17 : about 97kHz
+
+	wait := 1
+	if i2c.baudrate < 400*1e3 {
+		wait = 17
+	}
+
+	for i := 0; i < wait; i++ {
+		arm.Asm(`nop`)
+	}
+}