Hello, I am toggling two separate pins at different rates but it looks like for whatever reason the when I go to clear one gpio register it clears everything. I understand that writing a 0 to the outclr and dirset registers have no impact. so I am "OR" ing my OUT register with the specific bit I want to clear or set.
I am experiencing unusual behavior when I set the OUTCLR register. If the OUTCLR and out OUTSET are set to 0x1080 and I assert:
NRF_GPIO -> OUTCLR |= 0x80 I would expect this pin to go low and my other pin stays high but what happens is the registers go to 0.
This code works for one LED but when I introduced a timer interrupt to toggle a pin I encountered this unusual behavior. any ideas?
below is a snippet of my code
// simple function to toggle and led pin void toggle_led(uint8_t pin_number) {
if (ledpin == true) //if high turn off
{
NRF_GPIO -> OUTCLR |= (1 << pin_number);
ledpin = false;
}
else
{
NRF_GPIO -> OUTSET |= (1 << pin_number);
ledpin = true;
}
}
void TIMER0_IRQHandler(void) {
if (NRF_TIMER0->EVENTS_COMPARE[0] == 1)
{
if (((NRF_GPIO -> OUT & (1 << bitbang)) == 0) //low
NRF_GPIO-> OUTSET |= (1 << bitbang);
else //high capture event
{
val = (1<<HX711) & NRF_GPIO-> IN; // is it a 1 or 0?
val <<= 1; //left shift to get into place
NRF_GPIO-> OUTCLR |= (1 << bitbang);
}
NRF_TIMER0->EVENTS_COMPARE[0] = 0;
}
}
here is how my pins are configured {
#define bitbang 12
//bitbang clock. should create a clock of 80hz
define bitbang_DIR GPIO_PIN_CNF_DIR_Output
define bitbang_BUF GPIO_PIN_CNF_INPUT_Disconnect
define bitbang_PUL GPIO_PIN_CNF_PULL_Disabled
define bitbang_DRIVE GPIO_PIN_CNF_DRIVE_S0S1
define bitbang_SENSE GPIO_PIN_CNF_SENSE_Disabled
define HX711 11
define HX711_DIR GPIO_PIN_CNF_DIR_Input
define HX711_BUF GPIO_PIN_CNF_INPUT_Connect
define HX711_PUL GPIO_PIN_CNF_PULL_Disabled
define HX711_DRIVE GPIO_PIN_CNF_DRIVE_S0S1
define HX711_SENSE GPIO_PIN_CNF_SENSE_Disabled
#define bitbang_cfg (STPb_DIR << GPIO_PIN_CNF_DIR_Pos ) | ( STPb_BUF << GPIO_PIN_CNF_INPUT_Pos) | ( STPb_PUL << GPIO_PIN_CNF_PULL_Pos )| ( STPb_DRIVE << GPIO_PIN_CNF_DRIVE_Pos) | ( STPb_SENSE << GPIO_PIN_CNF_SENSE_Pos )
//bitbang clock pin
NRF_P0->PIN_CNF[bitbang] = bitbang_cfg;
//hx711 sensor
NRF_P0->PIN_CNF[HX711] = HX711_cfg;
} the names inside the PIN_CNF represent all of the above defines OR'd to create a word.
Thank you,
Eric Micallef
