fix starting level detection in pulse_reader

lib/pulse_reader/pulse_reader.c

@@ -137,9 +137,9 @@ void pulse_reader_start(PulseReader* signal) {
 
     /* capture current timer */
     signal->pos = 0;
-    signal->start_level = furi_hal_gpio_read(signal->gpio);
     signal->timer_value = TIM2->CNT;
     signal->gpio_mask = signal->gpio->pin;
+    signal->gpio_value = signal->gpio->port->IDR & signal->gpio_mask;
 
     /* now set up DMA with these settings */
     LL_DMA_Init(DMA1, signal->dma_channel, &signal->dma_config_timer);

lib/pulse_reader/pulse_reader.h

@@ -29,7 +29,6 @@ typedef enum {
 } PulseReaderUnit;
 
 typedef struct {
-    bool start_level;
     uint32_t* timer_buffer;
     uint32_t* gpio_buffer;
     uint32_t size;
@@ -65,7 +64,8 @@ void pulse_reader_free(PulseReader* signal);
 
 /** Start signal capturing
  *
- * Initializes DMA1, TIM2 and DMAMUX_REQ_GEN_0 to automatically capture timer values
+ * Initializes DMA1, TIM2 and DMAMUX_REQ_GEN_0 to automatically capture timer values.
+ * Ensure that interrupts are always enabled, as the used EXTI line is handled as one.
  *
  * @param[in]  signal      previously allocated PulseReader object.
  */