touchAttachInterrupt() userfunc parameter should not be void

[ericgu]

I'm working on some code that uses the touch subsystem and the arduino HAL.

I can call touchAttachInterrupt() multiple times for different pins. The underlying code in __touchISR() knows which routine to call for a specific pin, but it doesn't pass any pin information on.

This forces me to write something like:
touchAttachInterrupt(4, Touch0Interrupt, 20);
...
touchAttachment(32, Touch9Interrupt, 20);

touchAttachInterrupt() should store the pin number away at the same time it stores the function pointer away and then pass it on the callback. That would let me write a routine like:

void MyTouchHandler(int pinNumber)
{

}

and handle all the touch pins with a single chunk of generic code.

[sansillusion]

Not sure as I'm not much of a programmer but would something like that work ? :
touchAttachInterrupt(4, TouchInterrupt(0), 20);
touchAttachment(32, TouchInterrupt(9), 20);

[ericgu]

Unfortunately, that does not work, but you did get me thinking that I can probably do something with the C++ lambda support. Something like:

int pin = 32;
touchAttachInterrupt(pin, pin{MyInterruptHandler(pin);});

assuming I have my lambda syntax correct. That's not great but it's better than what I had planned from a syntax perspective, though the overhead might be worse...

Edit: there should be brackets around the second "pin".

[ericgu]

Lambdas do work but not in the format I used; you can't pass lambdas that do captures to function pointers, so they aren't really any better than my initial implementation.

[stale]

[STALE_SET] This issue has been automatically marked as stale because it has not had recent activity. It will be closed in 14 days if no further activity occurs. Thank you for your contributions.

[stale]

[STALE_DEL] This stale issue has been automatically closed. Thank you for your contributions.

[Leo-C]

Hi,
I believe that function esp_sleep_get_touchpad_wakeup_status() can help you.

Interrupt handler can not get a parameter indicating pin touched, but calling function above as first instruction, you'll have same information

Leonardo

[SuGlider]

New Touch API will have this function touchAttachInterruptArg(...)

/*
 * Set cycles that measurement operation takes
 * The result from touchRead, threshold and detection
 * accuracy depend on these values. Defaults are
 * 0x1000 for measure and 0x1000 for sleep.
 * With default values touchRead takes 0.5ms
 * */
void touchSetCycles(uint16_t measure, uint16_t sleep);

/*
 * Read touch pad (values close to 0 mean touch detected)
 * You can use this method to chose a good threshold value
 * to use as value for touchAttachInterrupt
 * */
uint32_t touchRead(uint8_t pin);

/*
 * Set function to be called if touch pad value falls (ESP32)
 * below the given threshold / rises (ESP32-S2/S3) by given increment (threshold). 
 * Use touchRead to determine a proper threshold between touched and untouched state
 * */
void touchAttachInterrupt(uint8_t pin, void (*userFunc)(void), uint32_t threshold);
void touchAttachInterruptArg(uint8_t pin, void (*userFunc)(void*), void *arg, uint32_t threshold);
void touchDetachInterrupt(uint8_t pin);

/*
 * Specific functions to ESP32 
 * Tells the dirver if it shall activate the ISR if the sensor is Lower or Higher than the Threshold
 * Default if Lower.
 **/
void touchInterruptSetThresholdDirection(bool mustbeLower);

[jdeltoft]

Does this new touchAttachInterruptArg() api support wake up from deep sleep? Or is that only supported with touchAttachInterrupt().

I have this for setup:

void setup() {
  touch_pad_init();

  for(int i=0; i<TOUCH_PIN_COUNT; i++) {
    touchAttachInterruptArg(pinNames[i], gotTouch, &pinIds[i], capTouchThreshold);
    touchSleepWakeUpEnable(pinNames[i], 500);
  }

  esp_sleep_enable_touchpad_wakeup();
}

And then if I call esp_deep_sleep_start(); I lose my serial connection and never seem to wake up from any touch. If I just remove this deep sleep call, everything works perfect for the 5 cap touch inputs.