Fix irremote reporting incorrect NEC addresses and command codes (#422)

Change from reading MSB->LSB to LSB->MSB
Fixes https://github.com/tinygo-org/drivers/issues/422

examples/irremote/main.go

@@ -8,27 +8,27 @@ import (
 )
 
 var irCmdButtons = map[uint16]string{
-	0xA2: "POWER",
-	0xE2: "FUNC/STOP",
-	0x62: "VOL+",
-	0x22: "FAST BACK",
-	0x02: "PAUSE",
-	0xC2: "FAST FORWARD",
-	0xE0: "DOWN",
-	0xA8: "VOL-",
-	0x90: "UP",
-	0x98: "EQ",
-	0xB0: "ST/REPT",
-	0x68: "0",
-	0x30: "1",
+	0x45: "POWER",
+	0x47: "FUNC/STOP",
+	0x46: "VOL+",
+	0x44: "FAST BACK",
+	0x40: "PAUSE",
+	0x43: "FAST FORWARD",
+	0x07: "DOWN",
+	0x15: "VOL-",
+	0x09: "UP",
+	0x19: "EQ",
+	0x0D: "ST/REPT",
+	0x16: "0",
+	0x0C: "1",
 	0x18: "2",
-	0x7A: "3",
-	0x10: "4",
-	0x38: "5",
+	0x5E: "3",
+	0x08: "4",
+	0x1C: "5",
 	0x5A: "6",
 	0x42: "7",
-	0x4A: "8",
-	0x52: "9",
+	0x52: "8",
+	0x4A: "9",
 }
 
 var (

irremote/receiver.go

@@ -151,7 +151,7 @@ func (ir *ReceiverDevice) pinChange(pin machine.Pin) {
 			ir.resetStateMachine()
 		} else {
 			// 562.5µs OR 1687.5µs space detected
-			mask := uint32((1 << (31 - ir.bitIndex)))
+			mask := uint32(1 << ir.bitIndex)
 			if duration > time.Microsecond*1000 {
 				// 1687.5µs space detected (logic 1) - Set bit
 				ir.data.Code |= mask
@@ -201,16 +201,16 @@ const (
 
 func (ir *ReceiverDevice) decode() irDecodeError {
 	// Decode cmd and inverse cmd and perform validation check
-	cmd := uint8((ir.data.Code & 0xff00) >> 8)
-	invCmd := uint8(ir.data.Code & 0xff)
+	cmd := uint8((ir.data.Code & 0x00ff0000) >> 16)
+	invCmd := uint8((ir.data.Code & 0xff000000) >> 24)
 	if cmd != ^invCmd {
 		// Validation failure. cmd and inverse cmd do not match
 		return irDecodeErrorInverseCheckFail
 	}
 	// cmd validation pass, decode address
 	ir.data.Command = uint16(cmd)
-	addrLow := uint8((ir.data.Code & 0xff000000) >> 24)
-	addrHigh := uint8((ir.data.Code & 0x00ff0000) >> 16)
+	addrLow := uint8(ir.data.Code & 0xff)
+	addrHigh := uint8((ir.data.Code & 0xff00) >> 8)
 	if addrHigh == ^addrLow {
 		// addrHigh is inverse of addrLow. This is not a valid 16-bit address in extended NEC coding
 		// since it is indistinguishable from 8-bit address with inverse validation. Use the 8-bit address