Dear all,
I'm using and nRF51822 chip for implementing a wireless HID device with dongle.
The device has an RGB LED, and indication scenarios for different modes are played using software PWM
(because nRF51 doesn't have hardware PWM, I use TIMER HW with 3 channels for each color).
And, I encounter the glitches in color scenarios when the Gazell stack is being used. I don't see any glitches when the Gazell is OFF. It's also OK when using BLE.
I suppose that it's a matter of configuring priorities for IRQs, and I've tried different configs for this, however, with no success.
Is this issue really solvable on nRF51 or it can only work smoothly on nRF52 with HW PWM?
Regards, Eugene
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The TIMER IRQ handler which makes the PWM
void led_event_handler(nrf_timer_event_t event_type, void* p_context)
{
switch (event_type)
{
case NRF_TIMER_EVENT_COMPARE0:
nrf_drv_gpiote_out_clear(GPIO_NRF_R_PIN_NUMBER);
nrf_drv_gpiote_out_clear(GPIO_NRF_G_PIN_NUMBER);
nrf_drv_gpiote_out_clear(GPIO_NRF_B_PIN_NUMBER);
break;
case NRF_TIMER_EVENT_COMPARE1:
nrf_drv_gpiote_out_set(GPIO_NRF_R_PIN_NUMBER);
break;
case NRF_TIMER_EVENT_COMPARE2:
nrf_drv_gpiote_out_set(GPIO_NRF_G_PIN_NUMBER);
break;
case NRF_TIMER_EVENT_COMPARE3:
nrf_drv_gpiote_out_set(GPIO_NRF_B_PIN_NUMBER);
break;
default:
break;
}
}
The color is being set using nrf_drv_timer_extended_compare function for each RGB component (TIMER channel)
