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//
// Arduino serial-interface for controlling 1 analog led strip. The serial interface is based on the
// Adalight protocol. The protocol is as follows:
// [prefix][led count][checksum][red, green, blue]*
// prefix := 'Ada'
// led count := number of leds - 1 (uint16_t big endian), unused in this case
// checksum := led count high bit XOR led count low bit XOR 0x55 (uint8_t)
// red, green, blue := channel intensity [0-255] (uint8_t)
//
/// The prefix for start sending led-data
static const uint8_t prefix[] = {'A', 'd', 'a'};
void setup()
{
// Open the serial-connection
Serial.begin(115200);
// Send 'Ada' string to host
Serial.print("Ada\n");
}
void loop()
{
int r, g, b;
// Wait for first byte of 'Ada'
for(int i = 0; i < sizeof(prefix); ++i)
{
while (!Serial.available());
// Check next byte in Magic Word
if(prefix[i] != Serial.read())
return;
}
// Wait for highByte, lowByte, Checksum to be available
while(Serial.available() < 3);
// Read high and low byte and the checksum
int highByte = Serial.read();
int lowByte = Serial.read();
int checksum = Serial.read();
if (checksum != (highByte ^ lowByte ^ 0x55))
{
// Checksum check failed
return;
}
// Wait for the next color spec to be available
while(Serial.available() < 3);
// Read the color spec
r = Serial.read();
g = Serial.read();
b = Serial.read();
analogWrite(3, r);
analogWrite(6, g);
analogWrite(5, b);
}
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