djsundog/circuitpython
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

esp32/espneopixel: Use integer arithmetic to compute timing values.

Browse Source
This commit is contained in:
Damien George 2020-04-09 09:49:29 +10:00
parent e292296d52
commit d6f80963df
1 changed files with 7 additions and 7 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

14
ports/esp32/espneopixel.c
View File

@ -20,18 +20,18 @@ void IRAM_ATTR esp_neopixel_write(uint8_t pin, uint8_t *pixels, uint32_t numByte
mask = 0x80;
startTime = 0;
uint32_t fcpu = ets_get_cpu_frequency() * 1000000;
uint32_t fcpu = ets_get_cpu_frequency();
if (timing == 1) {
// 800 KHz
time0 = (fcpu * 0.35) / 1000000; // 0.35us
time1 = (fcpu * 0.8) / 1000000; // 0.8us
period = (fcpu * 1.25) / 1000000; // 1.25us per bit
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 * 0.5) / 1000000; // 0.35us
time1 = (fcpu * 1.2) / 1000000; // 0.8us
period = (fcpu * 2.5) / 1000000; // 1.25us per bit
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();