Added TMC2209 support (#727)

TMC2209: Added TMC2209 support

tmc2209/current.go

@@ -0,0 +1,42 @@
+package tmc2209
+
+func Constrain(value, low, high uint32) uint32 {
+	if value < low {
+		return low
+	}
+	if value > high {
+		return high
+	}
+	return value
+}
+
+func SetRunCurrent(percent uint8) {
+	_ = PercentToCurrentSetting(percent)
+
+	// Set the run current register to runCurrent value
+}
+
+func SetHoldCurrent(percent uint8) {
+	_ = PercentToCurrentSetting(percent)
+	// Set the hold current register to holdCurrent value
+}
+func PercentToCurrentSetting(percent uint8) uint8 {
+	constrainedPercent := Constrain(uint32(percent), 0, 100)
+	return uint8(Map(constrainedPercent, 0, 100, 0, 255))
+}
+
+func CurrentSettingToPercent(currentSetting uint8) uint8 {
+	return uint8(Map(uint32(currentSetting), 0, 255, 0, 100))
+}
+
+func PercentToHoldDelaySetting(percent uint8) uint8 {
+	constrainedPercent := Constrain(uint32(percent), 0, 100)
+	return uint8(Map(constrainedPercent, 0, 100, 0, 255))
+}
+
+func HoldDelaySettingToPercent(holdDelaySetting uint8) uint8 {
+	return uint8(Map(uint32(holdDelaySetting), 0, 255, 0, 100))
+}
+func Map(value, fromLow, fromHigh, toLow, toHigh uint32) uint32 {
+	return (value-fromLow)*(toHigh-toLow)/(fromHigh-fromLow) + toLow
+}