75 lines
2.6 KiB
C
75 lines
2.6 KiB
C
// Original version from https://github.com/adafruit/Adafruit_NeoPixel
|
|
// Modifications by dpgeorge to support auto-CPU-frequency detection
|
|
|
|
// This is a mash-up of the Due show() code + insights from Michael Miller's
|
|
// ESP8266 work for the NeoPixelBus library: github.com/Makuna/NeoPixelBus
|
|
// Needs to be a separate .c file to enforce ICACHE_RAM_ATTR execution.
|
|
|
|
#include "py/mpconfig.h"
|
|
#include "py/mphal.h"
|
|
#include "modesp.h"
|
|
|
|
void IRAM_ATTR esp_neopixel_write(uint8_t pin, uint8_t *pixels, uint32_t numBytes, uint8_t timing) {
|
|
uint8_t *p, *end, pix, mask;
|
|
uint32_t t, time0, time1, period, c, startTime, pinMask, gpio_reg_set, gpio_reg_clear;
|
|
|
|
#if !CONFIG_IDF_TARGET_ESP32C3
|
|
if (pin >= 32) {
|
|
pinMask = 1 << (pin - 32);
|
|
gpio_reg_set = GPIO_OUT1_W1TS_REG;
|
|
gpio_reg_clear = GPIO_OUT1_W1TC_REG;
|
|
} else
|
|
#endif
|
|
{
|
|
pinMask = 1 << pin;
|
|
gpio_reg_set = GPIO_OUT_W1TS_REG;
|
|
gpio_reg_clear = GPIO_OUT_W1TC_REG;
|
|
}
|
|
p = pixels;
|
|
end = p + numBytes;
|
|
pix = *p++;
|
|
mask = 0x80;
|
|
startTime = 0;
|
|
|
|
uint32_t fcpu = ets_get_cpu_frequency();
|
|
|
|
if (timing == 1) {
|
|
// 800 KHz
|
|
time0 = (fcpu * 350) / 1000; // 0.35us
|
|
time1 = (fcpu * 800) / 1000; // 0.8us
|
|
period = (fcpu * 1250) / 1000; // 1.25us per bit
|
|
} else {
|
|
// 400 KHz
|
|
time0 = (fcpu * 500) / 1000; // 0.5us
|
|
time1 = (fcpu * 1200) / 1000; // 1.2us
|
|
period = (fcpu * 2500) / 1000; // 2.5us per bit
|
|
}
|
|
|
|
uint32_t irq_state = mp_hal_quiet_timing_enter();
|
|
for (t = time0;; t = time0) {
|
|
if (pix & mask) {
|
|
t = time1; // Bit high duration
|
|
}
|
|
while (((c = mp_hal_ticks_cpu()) - startTime) < period) {
|
|
; // Wait for bit start
|
|
}
|
|
GPIO_REG_WRITE(gpio_reg_set, pinMask); // Set high
|
|
startTime = c; // Save start time
|
|
while (((c = mp_hal_ticks_cpu()) - startTime) < t) {
|
|
; // Wait high duration
|
|
}
|
|
GPIO_REG_WRITE(gpio_reg_clear, pinMask); // Set low
|
|
if (!(mask >>= 1)) { // Next bit/byte
|
|
if (p >= end) {
|
|
break;
|
|
}
|
|
pix = *p++;
|
|
mask = 0x80;
|
|
}
|
|
}
|
|
while ((mp_hal_ticks_cpu() - startTime) < period) {
|
|
; // Wait for last bit
|
|
}
|
|
mp_hal_quiet_timing_exit(irq_state);
|
|
}
|