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337/*
* light weight WS2812 lib V2.0b
*
* Controls WS2811/WS2812/WS2812B RGB-LEDs
* Author: Tim (cpldcpu@gmail.com)
*
* Jan 18th, 2014 v2.0b Initial Version
* Nov 29th, 2015 v2.3 Added SK6812RGBW support
*
* License: GNU GPL v2+ (see License.txt)
https://cpldcpu.wordpress.com/2014/01/14/light_ws2812-library-v2-0-part-i-understanding-the-ws2812/
*/
#include "light_ws2812.h"
#include <avr/interrupt.h>
#include <avr/io.h>
#include <util/delay.h>
// Setleds for standard RGB
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_sendarray_mask((uint8_t*)ledarray,leds+leds+leds,pinmask);
_delay_us(ws2812_resettime);
}
// Setleds for SK6812RGBW
void /*inline*/ ws2812_setleds_rgbw(struct cRGBW *ledarray, uint16_t leds)
{
ws2812_sendarray_mask((uint8_t*)ledarray,leds<<2,_BV(ws2812_pin));
_delay_us(ws2812_resettime);
}
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;
ws2812_DDRREG |= maskhi; // Enable output
masklo =~maskhi&ws2812_PORTREG;
maskhi |= ws2812_PORTREG;
sreg_prev = SREG;
cli();
while (datlen--) {
curbyte=*data++;
asm volatile(
" ldi %0,8 \n\t" // loadImmediate 8 into ctr
"loop%=: \n\t"
" out %2,%3 \n\t" // '1' [01] '0' [01] - re // push HI out to port?
#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] // skip next instruction if bit7 set in data
" out %2,%4 \n\t" // '1' [--] '0' [03] - fe-low // push LOW out of led port ?
" lsl %1 \n\t" // '1' [04] '0' [04] // left shift data
#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 // push LOW out of led port ?
#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] // decrement counter
" brne loop%=\n\t" // '1' [+3] '0' [+4] // branch NEQ to loop
: "=&d" (ctr)
: "r" (curbyte), "I" (_SFR_IO_ADDR(ws2812_PORTREG)), "r" (maskhi), "r" (masklo)
);
}
SREG=sreg_prev;
}
#include <avr/pgmspace.h>
// passed as RGBW *only* to make the ASM math simpler (ie *4 == <<2 instead of *3)
void ws2812_sendarray_mask_palette(const struct cRGBW *userPaletteArray, const struct cRGBW *paletteArray, uint8_t *data, uint16_t datlen,unsigned char paletteDivLocal, uint8_t maskhi)
{
uint8_t curbyte, ctr, masklo;
uint8_t sreg_prev;
ws2812_DDRREG |= maskhi; // Enable output
masklo = ~maskhi&ws2812_PORTREG;
maskhi |= ws2812_PORTREG;
sreg_prev = SREG;
cli();
const uint8_t *componentDataAddress;
bool paletteInProgmemConfirmed;
while (datlen--)
{
// the "check which palette" logic pushed it over the edge (timewise) at 8mhz,
// increasing t0 16mhz made it happier
// check it's a user colour
if (*data & 0x10)
{
// get it back into the right range
componentDataAddress = (uint8_t*)&userPaletteArray[(*data)-16];
data++;
// can't be!
paletteInProgmemConfirmed = false;
}
else
{
componentDataAddress = (uint8_t*)&paletteArray[*data++];
// palette in progmem
paletteInProgmemConfirmed = true;
}
for (uint8_t component = 0; component < 3; component++)
{
if(paletteInProgmemConfirmed)
{
curbyte = pgm_read_byte(componentDataAddress++);
asm volatile(
" tst %0 \n\t"
" breq divDone%= \n\t" // if !curbyte skip the div
" mov r0, %2 \n\t" // move div into r0 (temp register) - marked as clobbered (1 cyc)
" tst r0 \n\t" // test it (1 cyc)
" breq divDone%= \n\t" // if it's 0 jump past div (1 cyc for failed, 2 for hit)
"divLoop%=: \n\t"
" lsr %0 \n\t" // div the byte by 2 (1 cyc)
" dec r0 \n\t" // dec (1 cyc)
" brne divLoop%= \n\t" // finished? (1 cyc for failed, 2 for hit)
// div = 0 : 4 cycles
// div = x : 3 + ( 4(x-1) + 3) [ 6 : 30 ] 30cycles is approx 4usec at 8mhz, well below the 10usec reset time
"divDone%=: \n\t"
: "=r" (curbyte)
: "0" (curbyte), "r" (paletteDivLocal)
: "r0"
);
}
else
{
curbyte = *componentDataAddress++;
}
asm volatile(
" ldi %0,8 \n\t" // loadImmediate 8 into ctr
"loop%=: \n\t"
" out %2,%3 \n\t" // '1' [01] '0' [01] - re // push HI out to port?
#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] // skip next instruction if bit7 set in data
" out %2,%4 \n\t" // '1' [--] '0' [03] - fe-low // push LOW out of led port ?
" lsl %1 \n\t" // '1' [04] '0' [04] // left shift data
#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 // push LOW out of led port ?
#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] // decrement counter
" brne loop%=\n\t" // '1' [+3] '0' [+4] // branch NEQ to loop
: "=&d" (ctr)
: "r" (curbyte), "I" (_SFR_IO_ADDR(ws2812_PORTREG)), "r" (maskhi), "r" (masklo)
);
}
}
SREG = sreg_prev;
}