Diff: LPD8806.cpp

Revision:

2:af5af64e114d

Parent:

1:6ebd3ac910b6

Child:

3:a415f73507c9

diff -r 6ebd3ac910b6 -r af5af64e114d LPD8806.cpp
--- a/LPD8806.cpp	Fri Dec 16 10:26:35 2011 +0000
+++ b/LPD8806.cpp	Sun Sep 16 13:09:54 2012 +0000
@@ -5,33 +5,40 @@
 // and their strips: http://www.adafruit.com/products/306
 // Released under the MIT License: http://mbed.org/license/mit
 //
-// standard connected to 1st hardware SPI
-// LPD8806  <> MBED
-// DATA     -> P5
-// CLOCK    -> p7
+// Parameterized and modified to use soft SPI.
+// Jas Strong <jasmine@electronpusher.org>
 /*****************************************************************************/
 
 #include "LPD8806.h"
 
-//Define SPI pins
-//Connected to first SPI module
-SPI spi(p5, p6, p7); // mosi, miso, sclk
-//SPI spi(p11, p12, p13); // mosi, miso, sclk
-
-LPD8806::LPD8806(uint16_t n) {
+LPD8806::LPD8806(PinName dataPin, PinName clockPin, int n) :
+    dat(dataPin),
+    clk(clockPin) {
     // Allocate 3 bytes per pixel:
+    numLEDs = n;
     if (NULL != (pixels = (uint8_t *)malloc(numLEDs * 3))) {
         memset(pixels, 0x80, numLEDs * 3); // Init to RGB 'off' state
-        numLEDs     = n;
     }
 }
 
-void LPD8806::begin(void) {
+/*
+ *  Soft SPI clock-out implementation (CPOL = 0, CPHA = 0).
+ *  Certainly not the fastest in the world but it'll do.
+ *  Gets about 3.6 MHz;  could get several times as much
+ *  using the bitbands directly  - jas.
+ */
+ 
+void LPD8806::write(uint8_t byte) {
+    for (int i=0; i<8; i++) {
+        clk = 0;
+        dat = (byte & 0x80);
+        clk = 1;
+        byte <<= 1;
+    }
+    clk = 0;
+}
 
-    // Setup the spi for 8 bit data, low steady state clock,
-    // first edge capture, with a 2MHz clock rate
-    spi.format(8,0);
-    spi.frequency(2000000);
+void LPD8806::begin(void) {
 
     // Issue initial latch to 'wake up' strip (latch length varies w/numLEDs)
     writezeros(3 * ((numLEDs + 63) / 64));
@@ -42,7 +49,11 @@
 }
 
 void LPD8806::writezeros(uint16_t n) {
-    while (n--) spi.write(0x00);
+    while (n--) write(0x00);
+}
+
+void LPD8806::blank(void) {
+    memset(pixels, 0x80, numLEDs * 3);
 }
 
 // This is how data is pushed to the strip.  Unfortunately, the company
@@ -53,15 +64,11 @@
     uint16_t i, nl3 = numLEDs * 3; // 3 bytes per LED
 
     for (i=0; i<nl3; i++ ) {
-        spi.write(pixels[i]);
+        write(pixels[i]);
     }
 
     // Write latch at end of data; latch length varies with number of LEDs
     writezeros(3 * ((numLEDs + 63) / 64));
-
-    // We need to have a delay here, a few ms seems to do the job
-    // shorter may be OK as well - need to experiment :(
-// wait_ms(3);
 }
 
 // Convert R,G,B to combined 32-bit color
@@ -81,6 +88,31 @@
     pixels[n*3+2] = b | 0x80;
 }
 
+void LPD8806::setPixelGB(uint16_t n, uint8_t g, uint8_t b) {
+    if (n >= numLEDs) return; // '>=' because arrays are 0-indexed
+
+    pixels[n*3  ] = g | 0x80;
+    pixels[n*3+2] = b | 0x80;
+}
+
+void LPD8806::setPixelR(uint16_t n, uint8_t r) {
+    if (n >= numLEDs) return; // '>=' because arrays are 0-indexed
+
+    pixels[n*3+1] = r | 0x80;
+}
+
+void LPD8806::setPixelG(uint16_t n, uint8_t g) {
+    if (n >= numLEDs) return; // '>=' because arrays are 0-indexed
+
+    pixels[n*3] = g | 0x80;
+}
+
+void LPD8806::setPixelB(uint16_t n, uint8_t b) {
+    if (n >= numLEDs) return; // '>=' because arrays are 0-indexed
+
+    pixels[n*3+2] = b | 0x80;
+}
+
 void LPD8806::setPixelColor(uint16_t n, uint32_t c) {
     if (n >= numLEDs) return; // '>=' because arrays are 0-indexed