Ned Konz / Mbed 2 deprecated Multi_WS2811_test

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Dependencies:   Multi_WS2811 mbed MMA8451Q

Fork of WS2811 by Heroic Robotics

WS2812.cpp@15:331e139672b5, 2013-12-05 (annotated)

Committer:
bikeNomad
Date:
Thu Dec 05 15:12:47 2013 +0000
Revision:
15:331e139672b5
inlined bit writes

Who changed what in which revision?

UserRevisionLine numberNew contents of line
bikeNomad 15:331e139672b5 1 // 800 KHz WS2812 driver, kinda.
bikeNomad 15:331e139672b5 2 //
bikeNomad 15:331e139672b5 3 // Parameterized and modified to use soft SPI.
bikeNomad 15:331e139672b5 4 // Jas Strong <jasmine@electronpusher.org>
bikeNomad 15:331e139672b5 5 // Modified to use hard SPI by Ned Konz <ned@bike-nomad.com>
bikeNomad 15:331e139672b5 6 /*****************************************************************************/
bikeNomad 15:331e139672b5 7
bikeNomad 15:331e139672b5 8 #include "LedStrip.h"
bikeNomad 15:331e139672b5 9 #include "WS2812.h"
bikeNomad 15:331e139672b5 10
bikeNomad 15:331e139672b5 11 WS2812::WS2812(int n, PinName mosi, PinName sclk) :
bikeNomad 15:331e139672b5 12 LedStrip(n),
bikeNomad 15:331e139672b5 13 spi(mosi, NC, sclk)
bikeNomad 15:331e139672b5 14 {
bikeNomad 15:331e139672b5 15 #ifdef TARGET_KL25Z
bikeNomad 15:331e139672b5 16 spi.format(8, 3);
bikeNomad 15:331e139672b5 17 #else
bikeNomad 15:331e139672b5 18 spi.format(16, 3);
bikeNomad 15:331e139672b5 19 #endif
bikeNomad 15:331e139672b5 20 spi.frequency(800e3 * 16); // 12.8 MHz => 800KHz bit rate
bikeNomad 15:331e139672b5 21 }
bikeNomad 15:331e139672b5 22
bikeNomad 15:331e139672b5 23 /*
bikeNomad 15:331e139672b5 24 * These chips use a one-wire protocol based on a sort of NRZ signalling- jas.
bikeNomad 15:331e139672b5 25 */
bikeNomad 15:331e139672b5 26
bikeNomad 15:331e139672b5 27 inline void WS2812::writebit(bool bit)
bikeNomad 15:331e139672b5 28 {
bikeNomad 15:331e139672b5 29 if (bit) {
bikeNomad 15:331e139672b5 30 #ifdef TARGET_KL25Z
bikeNomad 15:331e139672b5 31 spi.write(0xff); // 8 high
bikeNomad 15:331e139672b5 32 spi.write(0x00); // 8 low
bikeNomad 15:331e139672b5 33 #else
bikeNomad 15:331e139672b5 34 spi.write(0xff00);
bikeNomad 15:331e139672b5 35 #endif
bikeNomad 15:331e139672b5 36 } else {
bikeNomad 15:331e139672b5 37 #ifdef TARGET_KL25Z
bikeNomad 15:331e139672b5 38 spi.write(0xe0); // 3 high, 5 low
bikeNomad 15:331e139672b5 39 spi.write(0x00); // +8 low
bikeNomad 15:331e139672b5 40 #else
bikeNomad 15:331e139672b5 41 spi.write(0xe000);
bikeNomad 15:331e139672b5 42 #endif
bikeNomad 15:331e139672b5 43 }
bikeNomad 15:331e139672b5 44 }
bikeNomad 15:331e139672b5 45
bikeNomad 15:331e139672b5 46 void WS2812::write(uint8_t byte)
bikeNomad 15:331e139672b5 47 {
bikeNomad 15:331e139672b5 48 writebit(byte & 0x80);
bikeNomad 15:331e139672b5 49 writebit(byte & 0x40);
bikeNomad 15:331e139672b5 50 writebit(byte & 0x20);
bikeNomad 15:331e139672b5 51 writebit(byte & 0x10);
bikeNomad 15:331e139672b5 52 writebit(byte & 0x08);
bikeNomad 15:331e139672b5 53 writebit(byte & 0x04);
bikeNomad 15:331e139672b5 54 writebit(byte & 0x02);
bikeNomad 15:331e139672b5 55 writebit(byte & 0x01);
bikeNomad 15:331e139672b5 56 }
bikeNomad 15:331e139672b5 57
bikeNomad 15:331e139672b5 58 void WS2812::begin(void)
bikeNomad 15:331e139672b5 59 {
bikeNomad 15:331e139672b5 60 blank();
bikeNomad 15:331e139672b5 61 show();
bikeNomad 15:331e139672b5 62 }
bikeNomad 15:331e139672b5 63
bikeNomad 15:331e139672b5 64 void WS2812::blank(void)
bikeNomad 15:331e139672b5 65 {
bikeNomad 15:331e139672b5 66 memset(pixels, 0x00, numPixelBytes());
bikeNomad 15:331e139672b5 67 }
bikeNomad 15:331e139672b5 68
bikeNomad 15:331e139672b5 69 void WS2812::show(void)
bikeNomad 15:331e139672b5 70 {
bikeNomad 15:331e139672b5 71 uint16_t i, nl3 = numPixelBytes(); // 3 bytes per LED
bikeNomad 15:331e139672b5 72 while (guardtime.read_us() < 50)
bikeNomad 15:331e139672b5 73 /* spin */;
bikeNomad 15:331e139672b5 74 __disable_irq();
bikeNomad 15:331e139672b5 75 for (i=0; i<nl3; i++ ) {
bikeNomad 15:331e139672b5 76 write(pixels[i]);
bikeNomad 15:331e139672b5 77 }
bikeNomad 15:331e139672b5 78 __enable_irq();
bikeNomad 15:331e139672b5 79 guardtime.reset();
bikeNomad 15:331e139672b5 80 }
bikeNomad 15:331e139672b5 81
bikeNomad 15:331e139672b5 82