171 行
3.8 KiB
C
171 行
3.8 KiB
C
|
/*
|
||
|
* light weight WS2812 lib V2.0b
|
||
|
*
|
||
|
* Controls WS2811/WS2812/WS2812B RGB-LEDs
|
||
|
* Author: Tim (cpldcpu@gmail.com)
|
||
|
*
|
||
|
* Jan 18th, 2014 v2.0b Initial Version
|
||
|
*
|
||
|
* License: GNU GPL v2 (see License.txt)
|
||
|
*/
|
||
|
|
||
|
#include "light_ws2812.h"
|
||
|
#include <avr/interrupt.h>
|
||
|
#include <avr/io.h>
|
||
|
#include <util/delay.h>
|
||
|
|
||
|
void inline ws2812_setleds(struct cRGB *ledarray, uint16_t leds)
|
||
|
{
|
||
|
ws2812_setleds_pin(ledarray,leds, _BV(ws2812_pin));
|
||
|
}
|
||
|
|
||
|
void inline ws2812_setleds_pin(struct cRGB *ledarray, uint16_t leds, uint8_t pinmask)
|
||
|
{
|
||
|
ws2812_DDRREG |= pinmask; // Enable DDR
|
||
|
ws2812_sendarray_mask((uint8_t*)ledarray,leds+leds+leds,pinmask);
|
||
|
_delay_us(50);
|
||
|
}
|
||
|
|
||
|
void ws2812_sendarray(uint8_t *data,uint16_t datlen)
|
||
|
{
|
||
|
ws2812_sendarray_mask(data,datlen,_BV(ws2812_pin));
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
This routine writes an array of bytes with RGB values to the Dataout pin
|
||
|
using the fast 800kHz clockless WS2811/2812 protocol.
|
||
|
*/
|
||
|
|
||
|
// Timing in ns
|
||
|
#define w_zeropulse 350
|
||
|
#define w_onepulse 900
|
||
|
#define w_totalperiod 1250
|
||
|
|
||
|
// Fixed cycles used by the inner loop
|
||
|
#define w_fixedlow 2
|
||
|
#define w_fixedhigh 4
|
||
|
#define w_fixedtotal 8
|
||
|
|
||
|
// Insert NOPs to match the timing, if possible
|
||
|
#define w_zerocycles (((F_CPU/1000)*w_zeropulse )/1000000)
|
||
|
#define w_onecycles (((F_CPU/1000)*w_onepulse +500000)/1000000)
|
||
|
#define w_totalcycles (((F_CPU/1000)*w_totalperiod +500000)/1000000)
|
||
|
|
||
|
// w1 - nops between rising edge and falling edge - low
|
||
|
#define w1 (w_zerocycles-w_fixedlow)
|
||
|
// w2 nops between fe low and fe high
|
||
|
#define w2 (w_onecycles-w_fixedhigh-w1)
|
||
|
// w3 nops to complete loop
|
||
|
#define w3 (w_totalcycles-w_fixedtotal-w1-w2)
|
||
|
|
||
|
#if w1>0
|
||
|
#define w1_nops w1
|
||
|
#else
|
||
|
#define w1_nops 0
|
||
|
#endif
|
||
|
|
||
|
// The only critical timing parameter is the minimum pulse length of the "0"
|
||
|
// Warn or throw error if this timing can not be met with current F_CPU settings.
|
||
|
#define w_lowtime ((w1_nops+w_fixedlow)*1000000)/(F_CPU/1000)
|
||
|
#if w_lowtime>550
|
||
|
#error "Light_ws2812: Sorry, the clock speed is too low. Did you set F_CPU correctly?"
|
||
|
#elif w_lowtime>450
|
||
|
#warning "Light_ws2812: The timing is critical and may only work on WS2812B, not on WS2812(S)."
|
||
|
#warning "Please consider a higher clockspeed, if possible"
|
||
|
#endif
|
||
|
|
||
|
#if w2>0
|
||
|
#define w2_nops w2
|
||
|
#else
|
||
|
#define w2_nops 0
|
||
|
#endif
|
||
|
|
||
|
#if w3>0
|
||
|
#define w3_nops w3
|
||
|
#else
|
||
|
#define w3_nops 0
|
||
|
#endif
|
||
|
|
||
|
#define w_nop1 "nop \n\t"
|
||
|
#define w_nop2 "rjmp .+0 \n\t"
|
||
|
#define w_nop4 w_nop2 w_nop2
|
||
|
#define w_nop8 w_nop4 w_nop4
|
||
|
#define w_nop16 w_nop8 w_nop8
|
||
|
|
||
|
void inline ws2812_sendarray_mask(uint8_t *data,uint16_t datlen,uint8_t maskhi)
|
||
|
{
|
||
|
uint8_t curbyte,ctr,masklo;
|
||
|
uint8_t sreg_prev;
|
||
|
|
||
|
masklo =~maskhi&ws2812_PORTREG;
|
||
|
maskhi |= ws2812_PORTREG;
|
||
|
sreg_prev=SREG;
|
||
|
cli();
|
||
|
|
||
|
while (datlen--) {
|
||
|
curbyte=*data++;
|
||
|
|
||
|
asm volatile(
|
||
|
" ldi %0,8 \n\t"
|
||
|
"loop%=: \n\t"
|
||
|
" out %2,%3 \n\t" // '1' [01] '0' [01] - re
|
||
|
#if (w1_nops&1)
|
||
|
w_nop1
|
||
|
#endif
|
||
|
#if (w1_nops&2)
|
||
|
w_nop2
|
||
|
#endif
|
||
|
#if (w1_nops&4)
|
||
|
w_nop4
|
||
|
#endif
|
||
|
#if (w1_nops&8)
|
||
|
w_nop8
|
||
|
#endif
|
||
|
#if (w1_nops&16)
|
||
|
w_nop16
|
||
|
#endif
|
||
|
" sbrs %1,7 \n\t" // '1' [03] '0' [02]
|
||
|
" out %2,%4 \n\t" // '1' [--] '0' [03] - fe-low
|
||
|
" lsl %1 \n\t" // '1' [04] '0' [04]
|
||
|
#if (w2_nops&1)
|
||
|
w_nop1
|
||
|
#endif
|
||
|
#if (w2_nops&2)
|
||
|
w_nop2
|
||
|
#endif
|
||
|
#if (w2_nops&4)
|
||
|
w_nop4
|
||
|
#endif
|
||
|
#if (w2_nops&8)
|
||
|
w_nop8
|
||
|
#endif
|
||
|
#if (w2_nops&16)
|
||
|
w_nop16
|
||
|
#endif
|
||
|
" out %2,%4 \n\t" // '1' [+1] '0' [+1] - fe-high
|
||
|
#if (w3_nops&1)
|
||
|
w_nop1
|
||
|
#endif
|
||
|
#if (w3_nops&2)
|
||
|
w_nop2
|
||
|
#endif
|
||
|
#if (w3_nops&4)
|
||
|
w_nop4
|
||
|
#endif
|
||
|
#if (w3_nops&8)
|
||
|
w_nop8
|
||
|
#endif
|
||
|
#if (w3_nops&16)
|
||
|
w_nop16
|
||
|
#endif
|
||
|
|
||
|
" dec %0 \n\t" // '1' [+2] '0' [+2]
|
||
|
" brne loop%=\n\t" // '1' [+3] '0' [+4]
|
||
|
: "=&d" (ctr)
|
||
|
: "r" (curbyte), "I" (_SFR_IO_ADDR(ws2812_PORTREG)), "r" (maskhi), "r" (masklo)
|
||
|
);
|
||
|
}
|
||
|
|
||
|
SREG=sreg_prev;
|
||
|
}
|