From b541a2085a6a9303562d5f0ed302485463f3d74b Mon Sep 17 00:00:00 2001 From: David Madison Date: Tue, 20 Dec 2016 04:30:27 -0500 Subject: [PATCH] Added WS2812B Arduino code The initial modifications to the Adalight code to incorporate the FastLED library and work with WS2812B LEDs were done by James Bruce (@jamesabruce). I can't find a way to do a pull request on a Gist, so I'm copying his code in full here. Original Gist: https://gist.github.com/jamesabruce/09d79a56d270ed37870c --- .../LEDstream_WS2812B/LEDstream_WS2812B.ino | 166 ++++++++++++++++++ 1 file changed, 166 insertions(+) create mode 100644 Arduino/LEDstream_WS2812B/LEDstream_WS2812B.ino diff --git a/Arduino/LEDstream_WS2812B/LEDstream_WS2812B.ino b/Arduino/LEDstream_WS2812B/LEDstream_WS2812B.ino new file mode 100644 index 0000000..30e0d18 --- /dev/null +++ b/Arduino/LEDstream_WS2812B/LEDstream_WS2812B.ino @@ -0,0 +1,166 @@ +// Slightly modified Adalight protocol implementation that uses FastLED +// library (http://fastled.io) for driving WS2811/WS2812 led stripe +// Was tested only with Prismatik software from Lightpack project + +#include "FastLED.h" + +#define NUM_LEDS 114 // Max LED count +#define LED_PIN 6 // arduino output pin +#define GROUND_PIN 10 +#define BRIGHTNESS 255 // maximum brightness +#define SPEED 115200 // virtual serial port speed, must be the same in boblight_config + +CRGB leds[NUM_LEDS]; +uint8_t * ledsRaw = (uint8_t *)leds; + +// A 'magic word' (along with LED count & checksum) precedes each block +// of LED data; this assists the microcontroller in syncing up with the +// host-side software and properly issuing the latch (host I/O is +// likely buffered, making usleep() unreliable for latch). You may see +// an initial glitchy frame or two until the two come into alignment. +// The magic word can be whatever sequence you like, but each character +// should be unique, and frequent pixel values like 0 and 255 are +// avoided -- fewer false positives. The host software will need to +// generate a compatible header: immediately following the magic word +// are three bytes: a 16-bit count of the number of LEDs (high byte +// first) followed by a simple checksum value (high byte XOR low byte +// XOR 0x55). LED data follows, 3 bytes per LED, in order R, G, B, +// where 0 = off and 255 = max brightness. + +static const uint8_t magic[] = { + 'A','d','a'}; +#define MAGICSIZE sizeof(magic) +#define HEADERSIZE (MAGICSIZE + 3) + +#define MODE_HEADER 0 +#define MODE_DATA 2 + +// If no serial data is received for a while, the LEDs are shut off +// automatically. This avoids the annoying "stuck pixel" look when +// quitting LED display programs on the host computer. +static const unsigned long serialTimeout = 150000; // 150 seconds + +void setup() +{ + pinMode(GROUND_PIN, OUTPUT); + digitalWrite(GROUND_PIN, LOW); + FastLED.addLeds(leds, NUM_LEDS); + + // Dirty trick: the circular buffer for serial data is 256 bytes, + // and the "in" and "out" indices are unsigned 8-bit types -- this + // much simplifies the cases where in/out need to "wrap around" the + // beginning/end of the buffer. Otherwise there'd be a ton of bit- + // masking and/or conditional code every time one of these indices + // needs to change, slowing things down tremendously. + uint8_t + buffer[256], + indexIn = 0, + indexOut = 0, + mode = MODE_HEADER, + hi, lo, chk, i, spiFlag; + int16_t + bytesBuffered = 0, + hold = 0, + c; + int32_t + bytesRemaining; + unsigned long + startTime, + lastByteTime, + lastAckTime, + t; + int32_t outPos = 0; + + Serial.begin(SPEED); // Teensy/32u4 disregards baud rate; is OK! + + Serial.print("Ada\n"); // Send ACK string to host + + startTime = micros(); + lastByteTime = lastAckTime = millis(); + + // loop() is avoided as even that small bit of function overhead + // has a measurable impact on this code's overall throughput. + + for(;;) { + + // Implementation is a simple finite-state machine. + // Regardless of mode, check for serial input each time: + t = millis(); + if((bytesBuffered < 256) && ((c = Serial.read()) >= 0)) { + buffer[indexIn++] = c; + bytesBuffered++; + lastByteTime = lastAckTime = t; // Reset timeout counters + } + else { + // No data received. If this persists, send an ACK packet + // to host once every second to alert it to our presence. + if((t - lastAckTime) > 1000) { + Serial.print("Ada\n"); // Send ACK string to host + lastAckTime = t; // Reset counter + } + // If no data received for an extended time, turn off all LEDs. + if((t - lastByteTime) > serialTimeout) { + memset(leds, 0, NUM_LEDS * sizeof(struct CRGB)); //filling Led array by zeroes + FastLED.show(); + lastByteTime = t; // Reset counter + } + } + + switch(mode) { + + case MODE_HEADER: + + // In header-seeking mode. Is there enough data to check? + if(bytesBuffered >= HEADERSIZE) { + // Indeed. Check for a 'magic word' match. + for(i=0; (i 0) and multiply by 3 for R,G,B. + bytesRemaining = 3L * (256L * (long)hi + (long)lo + 1L); + bytesBuffered -= 3; + outPos = 0; + memset(leds, 0, NUM_LEDS * sizeof(struct CRGB)); + mode = MODE_DATA; // Proceed to latch wait mode + } + else { + // Checksum didn't match; search resumes after magic word. + indexOut -= 3; // Rewind + } + } // else no header match. Resume at first mismatched byte. + bytesBuffered -= i; + } + break; + + case MODE_DATA: + + if(bytesRemaining > 0) { + if(bytesBuffered > 0) { + if (outPos < sizeof(leds)) + ledsRaw[outPos++] = buffer[indexOut++]; // Issue next byte + bytesBuffered--; + bytesRemaining--; + } + // If serial buffer is threatening to underrun, start + // introducing progressively longer pauses to allow more + // data to arrive (up to a point). + } + else { + // End of data -- issue latch: + startTime = micros(); + mode = MODE_HEADER; // Begin next header search + FastLED.show(); + } + } // end switch + } // end for(;;) +} + +void loop() +{ + // Not used. See note in setup() function. +}