Revision 6:7aebe547f0f0, committed 2012-10-11

Comitter:

heroic

Date:

Thu Oct 11 08:34:21 2012 +0000

Parent:

5:70ded6500cd3

Child:

7:3025f0e0d70a

Commit message:

Initial commit of WS2801 driver library.

Changed in this revision

--- a/LPD8806.cpp	Wed Oct 10 05:43:58 2012 +0000
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,118 +0,0 @@
-// Mbed library to control LPD8806-based RGB LED Strips
-// (c) 2011 Jelmer Tiete
-// This library is ported from the Arduino implementation of Adafruit Industries
-// found at: http://github.com/adafruit/LPD8806
-// and their strips: http://www.adafruit.com/products/306
-// Released under the MIT License: http://mbed.org/license/mit
-//
-// Parameterized and modified to use soft SPI.
-// Jas Strong <jasmine@electronpusher.org>
-/*****************************************************************************/
-
-#include "LedStrip.h"
-#include "LPD8806.h"
-
-LPD8806::LPD8806(PinName dataPin, PinName clockPin, int n) :
-    dat(dataPin),
-    clk(clockPin) {
-    // Allocate 3 bytes per pixel:
-    numLEDs = n;
-    if ((pixels = (uint8_t *)malloc(numLEDs * 3))) {
-        memset(pixels, 0x80, numLEDs * 3); // Init to RGB 'off' state
-    }
-}
-
-/*
- *  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;
-}
-
-void LPD8806::begin(void) {
-
-    // Issue initial latch to 'wake up' strip (latch length varies w/numLEDs)
-    writezeros(3 * ((numLEDs + 63) / 64));
-    blank();
-    show();
-}
-
-uint16_t LPD8806::numPixels(void) {
-    return numLEDs;
-}
-
-void LPD8806::writezeros(uint16_t n) {
-    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
-// that makes the chip didnt release the  protocol document or you need
-// to sign an NDA or something stupid like that, but we reverse engineered
-// this from a strip controller and it seems to work very nicely!
-void LPD8806::show(void) {
-    uint16_t i, nl3 = numLEDs * 3; // 3 bytes per LED
-
-    for (i=0; i<nl3; i++ ) {
-        write(pixels[i]);
-    }
-
-    // Write latch at end of data; latch length varies with number of LEDs
-    writezeros(3 * ((numLEDs + 63) / 64));
-}
-
-// Convert R,G,B to combined 32-bit color
-uint32_t LPD8806::Color(uint8_t r, uint8_t g, uint8_t b) {
-    // Take the lowest 7 bits of each value and append them end to end
-    // We have the top bit set high (its a 'parity-like' bit in the protocol
-    // and must be set!)
-    return 0x808080 | ((uint32_t)g << 16) | ((uint32_t)r << 8) | (uint32_t)b;
-}
-
-// store the rgb component in our array
-void LPD8806::setPixelColor(uint16_t n, uint8_t r, uint8_t g, uint8_t b) {
-    if (n >= numLEDs) return; // '>=' because arrays are 0-indexed
-
-    pixels[n*3  ] = g | 0x80;
-    pixels[n*3+1] = r | 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
-
-    pixels[n*3  ] = (c >> 16) | 0x80;
-    pixels[n*3+1] = (c >>  8) | 0x80;
-    pixels[n*3+2] =  c        | 0x80;
-}

--- a/LPD8806.h	Wed Oct 10 05:43:58 2012 +0000
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,44 +0,0 @@
-// Mbed library to control LPD8806-based RGB LED Strips
-// (c) 2011 Jelmer Tiete
-// This library is ported from the Arduino implementation of Adafruit Industries
-// found at: http://github.com/adafruit/LPD8806
-// and their strips: http://www.adafruit.com/products/306
-// Released under the MIT License: http://mbed.org/license/mit
-//
-/*****************************************************************************/
-
-// Heavily modified by Jas Strong, 2012-10-04
-// Changed to use a virtual base class and to use software SPI.
-
-#include "mbed.h"
-#include "LedStrip.h"
-#ifndef MBED_LPD8806_H
-#define MBED_LPD8806_H
-
-class LPD8806 : public LedStrip {
-
- public:
-
-  LPD8806(PinName dataPin, PinName clockPin, int n);
-  virtual void begin(void);
-  virtual void show(void);
-  virtual void blank(void);
-  virtual void setPixelColor(uint16_t n, uint8_t r, uint8_t g, uint8_t b);
-  virtual void setPixelB(uint16_t n, uint8_t b);
-  virtual void setPixelG(uint16_t n, uint8_t g);
-  virtual void setPixelR(uint16_t n, uint8_t r);
-  virtual void setPixelColor(uint16_t n, uint32_t c);
-  virtual uint16_t numPixels(void);
-  virtual uint32_t Color(uint8_t, uint8_t, uint8_t);
-
- private:
-  DigitalOut dat;
-  DigitalOut clk;
-  void write(uint8_t byte);
-  uint8_t *pixels;     // Holds LED color values
-  uint16_t numLEDs;     // Number of RGB LEDs in strand
-    
-  void
-    writezeros(uint16_t n);
-};
-#endif
\ No newline at end of file

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/WS2801.cpp	Thu Oct 11 08:34:21 2012 +0000
@@ -0,0 +1,114 @@
+// Mbed library to control LPD8806-based RGB LED Strips
+// (c) 2011 Jelmer Tiete
+// This library is ported from the Arduino implementation of Adafruit Industries
+// found at: http://github.com/adafruit/LPD8806
+// and their strips: http://www.adafruit.com/products/306
+// Released under the MIT License: http://mbed.org/license/mit
+//
+// Parameterized and modified to use soft SPI.
+// Jas Strong <jasmine@electronpusher.org>
+/*****************************************************************************/
+
+#include "LedStrip.h"
+#include "WS2801.h"
+
+WS2801::WS2801(PinName dataPin, PinName clockPin, int n) :
+    dat(dataPin),
+    clk(clockPin) {
+    // Allocate 3 bytes per pixel:
+    numLEDs = n;
+    if ((pixels = (uint8_t *)malloc(numLEDs * 3))) {
+        memset(pixels, 0x00, numLEDs * 3); // Init to RGB 'off' state
+    }
+    guardtime.start();
+}
+
+/*
+ *  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 WS2801::write(uint8_t byte) {
+    for (int i=0; i<8; i++) {
+        clk = 0;
+        wait_us(WS2801_DELAY);
+        dat = (byte & 0x80);
+        clk = 1;
+        wait_us(WS2801_DELAY);
+        byte <<= 1;
+    }
+    clk = 0;
+}
+
+void WS2801::begin(void) {
+    blank();
+    show();
+}
+
+uint16_t WS2801::numPixels(void) {
+    return numLEDs;
+}
+
+void WS2801::blank(void) {
+    memset(pixels, 0x00, numLEDs * 3);
+}
+
+// This is how data is pushed to the strip.  Unfortunately, the company
+// that makes the chip didnt release the  protocol document or you need
+// to sign an NDA or something stupid like that, but we reverse engineered
+// this from a strip controller and it seems to work very nicely!
+void WS2801::show(void) {
+    uint16_t i, nl3 = numLEDs * 3; // 3 bytes per LED
+    while (guardtime.read_us() < 500)
+        /* spin */;
+    for (i=0; i<nl3; i++ ) {
+        write(pixels[i]);
+    }
+
+    guardtime.reset();
+}
+
+// Convert R,G,B to combined 32-bit color
+uint32_t WS2801::Color(uint8_t r, uint8_t g, uint8_t b) {
+    // Take the lowest 7 bits of each value and append them end to end
+    // We have the top bit set high (its a 'parity-like' bit in the protocol
+    // and must be set!)
+    return ((uint32_t)g << 16) | ((uint32_t)r << 8) | (uint32_t)b;
+}
+
+// store the rgb component in our array
+void WS2801::setPixelColor(uint16_t n, uint8_t r, uint8_t g, uint8_t b) {
+    if (n >= numLEDs) return; // '>=' because arrays are 0-indexed
+
+    pixels[n*3  ] = g;
+    pixels[n*3+1] = r;
+    pixels[n*3+2] = b;
+}
+
+void WS2801::setPixelR(uint16_t n, uint8_t r) {
+    if (n >= numLEDs) return; // '>=' because arrays are 0-indexed
+
+    pixels[n*3+1] = r;
+}
+
+void WS2801::setPixelG(uint16_t n, uint8_t g) {
+    if (n >= numLEDs) return; // '>=' because arrays are 0-indexed
+
+    pixels[n*3] = g;
+}
+
+void WS2801::setPixelB(uint16_t n, uint8_t b) {
+    if (n >= numLEDs) return; // '>=' because arrays are 0-indexed
+
+    pixels[n*3+2] = b;
+}
+
+void WS2801::setPixelColor(uint16_t n, uint32_t c) {
+    if (n >= numLEDs) return; // '>=' because arrays are 0-indexed
+
+    pixels[n*3  ] = (c >> 16);
+    pixels[n*3+1] = (c >>  8);
+    pixels[n*3+2] =  c;
+}

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/WS2801.h	Thu Oct 11 08:34:21 2012 +0000
@@ -0,0 +1,45 @@
+// Mbed library to control WS2801-based RGB LED Strips
+// some portions (c) 2011 Jelmer Tiete
+// This library is ported from the Arduino implementation of Adafruit Industries
+// found at: http://github.com/adafruit/LPD8806
+// and their strips: http://www.adafruit.com/products/306
+// Released under the MIT License: http://mbed.org/license/mit
+//
+/*****************************************************************************/
+
+// Heavily modified by Jas Strong, 2012-10-04
+// Changed to use a virtual base class and to use software SPI.
+
+#include "mbed.h"
+#include "LedStrip.h"
+#ifndef MBED_WS2801_H
+#define MBED_WS2801_H
+
+#define WS2801_DELAY 1
+
+class WS2801 : public LedStrip {
+
+ public:
+
+  WS2801(PinName dataPin, PinName clockPin, int n);
+  virtual void begin(void);
+  virtual void show(void);
+  virtual void blank(void);
+  virtual void setPixelColor(uint16_t n, uint8_t r, uint8_t g, uint8_t b);
+  virtual void setPixelB(uint16_t n, uint8_t b);
+  virtual void setPixelG(uint16_t n, uint8_t g);
+  virtual void setPixelR(uint16_t n, uint8_t r);
+  virtual void setPixelColor(uint16_t n, uint32_t c);
+  virtual uint16_t numPixels(void);
+  virtual uint32_t Color(uint8_t, uint8_t, uint8_t);
+
+ private:
+  DigitalOut dat;
+  DigitalOut clk;
+  void write(uint8_t byte);
+  uint8_t *pixels;     // Holds LED color values
+  uint16_t numLEDs;     // Number of RGB LEDs in strand
+  Timer guardtime;
+    
+};
+#endif
\ No newline at end of file