Alan Rager
This library controls a strip of apa102 lights. It is heavily based on https://developer.mbed.org/users/wertyfrog/code/ws2801/ and is a little messy looking since my coding style does not match Mr Olsson's. It should work the same as Olsson's lib, and I'm definitely going to add more dox later.
Diff: apa102.cpp
- Revision:
- 0:cd4bcb59e36e
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/apa102.cpp Tue Jan 27 17:33:01 2015 +0000
@@ -0,0 +1,80 @@
+#include "apa102.h"
+#include "mbed.h"
+
+#define DO_N(N, F) for( int repetier = 0; repetier < N; repetier++) { F; }
+
+//------------------------------------------------------------------------------------------------------------
+apa102::apa102(PinName CKI, PinName SDI, int STRIP_LENGTH, int reset_delay)
+: _CKI(CKI), _SDI(SDI), _STRIP_LENGTH(STRIP_LENGTH), _reset_delay(reset_delay) {
+
+ _level=100;
+ this->clear();
+ wait_us(_reset_delay);
+}
+//------------------------------------------------------------------------------------------------------------
+void apa102::post(int *strip_colors) {
+ this->preamble();
+
+ int scaled_level = 0xE0 | (_level * 31 / 100);
+
+ for(int LED_number = 0 ; LED_number < _STRIP_LENGTH ; LED_number++) {
+ this->write_word(scaled_level, 8);
+ this->write_word(strip_colors[LED_number], 24);
+ }
+
+ this->afterword();
+ wait_us(_reset_delay); //Wait for 1ms to go into reset
+}
+//------------------------------------------------------------------------------------------------------------
+void apa102::clear(void) {
+ this->preamble();
+ DO_N(_STRIP_LENGTH, this->write_word(0xE0000000, 32));
+ this->afterword();
+}
+//------------------------------------------------------------------------------------------------------------
+int apa102::level(int level)
+{
+if((level <= 100) && level)
+ {
+ _level = level;
+ return _level;
+ }
+return 0;
+}
+
+//------------------------------------------------------------------------------------------------------------
+int apa102::delay(uint32_t reset_delay)
+{
+if(reset_delay <= 0xffffffff)_reset_delay = reset_delay;
+return _reset_delay;
+}
+//------------------------------------------------------------------------------------------------------------
+inline void apa102::write_hi() {
+ this->write_bit(1);
+}
+inline void apa102::write_lo() {
+ this->write_bit(0);
+}
+inline void apa102::write_bit(bool bit) {
+ _CKI = 0;
+ _SDI = bit;
+ _CKI = 1;
+}
+inline void apa102::write_word(uint32_t word, int bits) {
+ for(char color_bit = bits - 1 ; color_bit != 255 ; color_bit--) {
+ this->write_bit(
+ (word & (1 << color_bit)) ? 1 : 0
+ );
+ }
+}
+inline void apa102::write_done() {
+ _CKI = 0;
+}
+inline void apa102::preamble() {
+ DO_N(32, this->write_lo());
+}
+inline void apa102::afterword() {
+ DO_N(32, this->write_hi());
+ this->write_done();
+}
+//---------EOF---------------EOF------------------------------------------------------------------------------
\ No newline at end of file