Delay Microseconds Function [SOLVED]

[jfox]

I was wondering if anyone could point me to the correct location of a delay microseconds function within the existing firmware. I’m working with a Photon and am trying to develop a 1-wire master with software for educational purposes. I need a reliable way to get timings in microseconds. I found the HAL_Delay_Microseconds in /hal/inc/delay_hal.h, but there doesn’t seem to be an implementation in /hal/src/photon/delay_hal.c and I’m not even sure if this is the correct function to use to begin with. Any help on the matter would be greatly appreciated.

[peekay123]

@jfox, you can use the wiring function delayMicroseconds() or for non-blocking code, you can use micros(). Take a look at this topic about 2/3 down for inspiration if you need you own custom function:

Micros() rolling over after 59.652323 seconds, not 71 minutes [SOLVED]

I’m running the following code: void setup (void) { Serial.begin(38400); } void loop (void) { Serial.println ("millis() = " + String(millis()) + "micros() = " + String(micros())); delay (1000); } Produces the following results: millis = 57996, micros = 58017760 millis = 59004, micros = 59025514 millis = 60013, micros = 381959 millis = 61020, micros = 1389481 millis = 62029, micros = 2398259 millis = 63038, micros = 3407027 millis = 116470, micros = 56839482 millis = 117479, mic…

[mdma]

@jfox

HAL_Delay_Microseconds in /hal/inc/delay_hal.h

That's the correct function to use. The implementation is here:

https://github.com/spark/firmware/blob/develop/hal/src/stm32f2xx/delay_hal_stm32f2xx.c#L38