LED-Mesh/libraries/FastLED/platforms/arm/sam/clockless_arm_sam.h
2019-02-13 22:27:19 +01:00

121 lines
3.6 KiB
C++

#ifndef __INC_CLOCKLESS_ARM_SAM_H
#define __INC_CLOCKLESS_ARM_SAM_H
FASTLED_NAMESPACE_BEGIN
// Definition for a single channel clockless controller for the sam family of arm chips, like that used in the due and rfduino
// See clockless.h for detailed info on how the template parameters are used.
#if defined(__SAM3X8E__)
#define TADJUST 0
#define TOTAL ( (T1+TADJUST) + (T2+TADJUST) + (T3+TADJUST) )
#define FASTLED_HAS_CLOCKLESS 1
template <uint8_t DATA_PIN, int T1, int T2, int T3, EOrder RGB_ORDER = RGB, int XTRA0 = 0, bool FLIP = false, int WAIT_TIME = 50>
class ClocklessController : public CPixelLEDController<RGB_ORDER> {
typedef typename FastPinBB<DATA_PIN>::port_ptr_t data_ptr_t;
typedef typename FastPinBB<DATA_PIN>::port_t data_t;
data_t mPinMask;
data_ptr_t mPort;
CMinWait<WAIT_TIME> mWait;
public:
virtual void init() {
FastPinBB<DATA_PIN>::setOutput();
mPinMask = FastPinBB<DATA_PIN>::mask();
mPort = FastPinBB<DATA_PIN>::port();
}
virtual uint16_t getMaxRefreshRate() const { return 400; }
protected:
virtual void showPixels(PixelController<RGB_ORDER> & pixels) {
mWait.wait();
if(!showRGBInternal(pixels)) {
sei(); delayMicroseconds(WAIT_TIME); cli();
showRGBInternal(pixels);
}
mWait.mark();
}
template<int BITS> __attribute__ ((always_inline)) inline static void writeBits(register uint32_t & next_mark, register data_ptr_t port, register uint8_t & b) {
// Make sure we don't slot into a wrapping spot, this will delay up to 12.5µs for WS2812
// bool bShift=0;
// while(VAL < (TOTAL*10)) { bShift=true; }
// if(bShift) { next_mark = (VAL-TOTAL); };
for(register uint32_t i = BITS; i > 0; i--) {
// wait to start the bit, then set the pin high
while(DUE_TIMER_VAL < next_mark);
next_mark = (DUE_TIMER_VAL+TOTAL);
*port = 1;
// how long we want to wait next depends on whether or not our bit is set to 1 or 0
if(b&0x80) {
// we're a 1, wait until there's less than T3 clocks left
while((next_mark - DUE_TIMER_VAL) > (T3));
} else {
// we're a 0, wait until there's less than (T2+T3+slop) clocks left in this bit
while((next_mark - DUE_TIMER_VAL) > (T2+T3+6+TADJUST+TADJUST));
}
*port=0;
b <<= 1;
}
}
#define FORCE_REFERENCE(var) asm volatile( "" : : "r" (var) )
// This method is made static to force making register Y available to use for data on AVR - if the method is non-static, then
// gcc will use register Y for the this pointer.
static uint32_t showRGBInternal(PixelController<RGB_ORDER> pixels) {
// Setup and start the clock
TC_Configure(DUE_TIMER,DUE_TIMER_CHANNEL,TC_CMR_TCCLKS_TIMER_CLOCK1);
pmc_enable_periph_clk(DUE_TIMER_ID);
TC_Start(DUE_TIMER,DUE_TIMER_CHANNEL);
register data_ptr_t port asm("r7") = FastPinBB<DATA_PIN>::port(); FORCE_REFERENCE(port);
*port = 0;
// Setup the pixel controller and load/scale the first byte
pixels.preStepFirstByteDithering();
uint8_t b = pixels.loadAndScale0();
uint32_t next_mark = (DUE_TIMER_VAL + (TOTAL));
while(pixels.has(1)) {
pixels.stepDithering();
#if (FASTLED_ALLOW_INTERRUPTS == 1)
cli();
if(DUE_TIMER_VAL > next_mark) {
if((DUE_TIMER_VAL - next_mark) > ((WAIT_TIME-INTERRUPT_THRESHOLD)*CLKS_PER_US)) { sei(); TC_Stop(DUE_TIMER,DUE_TIMER_CHANNEL); return 0; }
}
#endif
writeBits<8+XTRA0>(next_mark, port, b);
b = pixels.loadAndScale1();
writeBits<8+XTRA0>(next_mark, port,b);
b = pixels.loadAndScale2();
writeBits<8+XTRA0>(next_mark, port,b);
b = pixels.advanceAndLoadAndScale0();
#if (FASTLED_ALLOW_INTERRUPTS == 1)
sei();
#endif
};
TC_Stop(DUE_TIMER,DUE_TIMER_CHANNEL);
return DUE_TIMER_VAL;
}
};
#endif
FASTLED_NAMESPACE_END
#endif