Add pulse counter feature to RS41ng (#20)

* Started pulse counter implementation

* Update horus_packet_v2.c

* Update horus_packet_v2.c

* Added external bool

* Added pulse count variables for APRS/CW

* Ext Interrupt implementation

* Update pulse_counter.c

* Counter tests

* Update pulse_counter.c

That's what happens when I copy/paste code without triple checking it first...

* Fixed some mistakes

* Interrupt implementation

* More fixes

* Update pulse_counter.c

* Update pulse_counter.c

* Added some interlocks for I2C and UART

* Fixed Interrupts

Now working - need to check the impact on other devices...

* Update horus_packet_v2.c

Forgot to increase the pointer - it kept re-writing the mbar value...

* Code reformatting

* Clean up code and add docs

* Pulse counter WIP

* Add more documentation

Co-authored-by: Mikael Nousiainen <mikael.nousiainen@iki.fi>

README.md

@@ -67,6 +67,7 @@ The main features the RS41ng firmware are:
 * Support for transmitting multiple modes consecutively with custom, rotating comment messages (see `config.c`)
 * Support for GPS-based scheduling is available for transmission modes that require specific timing for transmissions
 * Support for custom sensors via the external I²C bus
+* Support for counting pulses on expansion header pin 2 (I2C2_SDA (PB11) / UART3 RX) for use with sensors like Geiger counters
 * GPS NMEA data output via the external serial port pin 3 (see below). This disables use of I²C devices as the serial port pins are shared with the I²C bus pins.
   * This allows using the RS41 sonde GPS data in external tracker hardware, such as Raspberry Pi or other microcontrollers.
 * Enhanced support for the internal Si4032 radio transmitter via PWM-based tone generation (and ultimately DMA-based symbol timing, if possible)
@@ -200,6 +201,7 @@ ______________________|           |______________________
 * 1 - GND
 * 2 - I2C2_SDA (PB11) / UART3 RX
     * This is the external I²C port data pin for Si5351 and sensors
+    * This pin can be used as input for the pulse counter.
 * 3 - I2C2_SCL (PB10) / UART3 TX
     * This is the external I²C port clock pin for Si5351 and sensors
     * This pin can alternatively be used to output GPS NMEA data to external tracker hardware (e.g. Raspberry Pi or other microcontrollers)

src/codecs/horus/horus_packet_v2.c

@@ -1,6 +1,7 @@
 #include <string.h>
 #include "horus_packet_v2.h"
 #include "horus_common.h"
+#include "config.h"
 
 volatile uint16_t horus_v2_packet_counter = 0;
 
@@ -15,7 +16,7 @@ size_t horus_packet_v2_create(uint8_t *payload, size_t length, telemetry_data *d
     float float_lat = (float) gps_data->latitude_degrees_1000000 / 10000000.0f;
     float float_lon = (float) gps_data->longitude_degrees_1000000 / 10000000.0f;
 
-    uint8_t volts_scaled = (uint8_t)(255 * (float) data->battery_voltage_millivolts / 5000.0f);
+    uint8_t volts_scaled = (uint8_t) (255 * (float) data->battery_voltage_millivolts / 5000.0f);
 
     horus_v2_packet_counter++;
 
@@ -29,8 +30,8 @@ size_t horus_packet_v2_create(uint8_t *payload, size_t length, telemetry_data *d
     horus_packet.Seconds = gps_data->seconds;
     horus_packet.Latitude = float_lat;
     horus_packet.Longitude = float_lon;
-    horus_packet.Altitude = (uint16_t)((gps_data->altitude_mm > 0 ? gps_data->altitude_mm : 0) / 1000);
+    horus_packet.Altitude = (uint16_t) ((gps_data->altitude_mm > 0 ? gps_data->altitude_mm : 0) / 1000);
-    horus_packet.Speed = (uint8_t)((float) gps_data->ground_speed_cm_per_second * 0.036);
+    horus_packet.Speed = (uint8_t) ((float) gps_data->ground_speed_cm_per_second * 0.036);
 
     horus_packet.BattVoltage = volts_scaled;
     horus_packet.Sats = gps_data->satellites_visible;
@@ -66,7 +67,13 @@ size_t horus_packet_v2_create(uint8_t *payload, size_t length, telemetry_data *d
     // Unit: mbar * 10
     uint16_t ext_pressure_mbar = (uint16_t) (data->pressure_mbar_100 / 10.0f);
     memcpy(custom_data_pointer, &ext_pressure_mbar, sizeof(ext_pressure_mbar));
-    // custom_data_pointer += sizeof(ext_pressure_mbar);
+
+    if (pulse_counter_enabled) {
+        // Unit: pulse count
+        custom_data_pointer += sizeof(ext_pressure_mbar);
+        uint16_t ext_pulse_count = (uint16_t) data->pulse_count;
+        memcpy(custom_data_pointer, &ext_pulse_count, sizeof(ext_pulse_count));
+    }
 
     horus_packet.Checksum = (uint16_t) calculate_crc16_checksum((char *) &horus_packet,
             sizeof(horus_packet) - sizeof(horus_packet.Checksum));

src/config.c

@@ -25,6 +25,7 @@
  * $gs - Ground speed in km/h (up to 3 chars)
  * $cl - Climb in m/s (up to 2 chars)
  * $he - Heading in degrees (up to 3 chars)
+ * $pc - Pulse counter value (wraps to zero at 65535, 16-bit unsigned value)
  *
  * Allowed message lengths:
  *
@@ -44,6 +45,7 @@ bool leds_enabled = LEDS_ENABLE;
 bool bmp280_enabled = SENSOR_BMP280_ENABLE;
 bool si5351_enabled = RADIO_SI5351_ENABLE;
 bool gps_nmea_output_enabled = GPS_NMEA_OUTPUT_VIA_SERIAL_PORT_ENABLE;
+bool pulse_counter_enabled = PULSE_COUNTER_ENABLE;
 
 volatile bool system_initialized = false;
 

src/config.h

@@ -55,6 +55,33 @@
 #error GPS NMEA output via serial port cannot be enabled simultaneously with the I2C bus.
 #endif
 
+// Enable pulse counter via expansion header pin for use with devices like Geiger counters.
+// This disables the external I²C bus and the serial port as the expansion header pin 2 (I2C2_SDA (PB11) / UART3 RX) is used for pulse input.
+// Also changes the Horus 4FSK V2 data format and adds a custom data field for pulse count.
+// The pulse count will wrap to zero at 65535 as it is stored as a 16-bit unsigned integer value.
+#define PULSE_COUNTER_ENABLE false
+
+// Pulse counter pin modes
+#define PULSE_COUNTER_PIN_MODE_FLOATING 0
+#define PULSE_COUNTER_PIN_MODE_INTERNAL_PULL_UP 1
+#define PULSE_COUNTER_PIN_MODE_INTERNAL_PULL_DOWN 2
+
+// Enable the internal pull-up or pull-down resistor on expansion header pin 2 (I2C2_SDA (PB11) / UART3 RX)
+// This is necessary if the pulse counter needs to count pulses where the pin is pulled low (ground) or high (VCC) during the pulse.
+// Set to "floating" if the circuit that generates the pulses already has a pull-up or a pull-down resistor.
+#define PULSE_COUNTER_PIN_MODE PULSE_COUNTER_PIN_MODE_INTERNAL_PULL_UP
+
+// Pulse counter interrupt edges
+#define PULSE_COUNTER_INTERRUPT_EDGE_FALLING 1
+#define PULSE_COUNTER_INTERRUPT_EDGE_RISING 2
+
+// Set the edge of the pulse where the interrupt is triggered: falling or rising.
+#define PULSE_COUNTER_INTERRUPT_EDGE PULSE_COUNTER_INTERRUPT_EDGE_FALLING
+
+#if (PULSE_COUNTER_ENABLE) && ((GPS_NMEA_OUTPUT_VIA_SERIAL_PORT_ENABLE) || (RADIO_SI5351_ENABLE) || (SENSOR_BMP280_ENABLE))
+#error Pulse counter cannot be enabled simultaneously with GPS NMEA output or I2C bus sensors.
+#endif
+
 /**
  * Built-in Si4032 radio chip transmission configuration
  */

src/config_internal.h

@@ -19,6 +19,7 @@ extern bool leds_enabled;
 extern bool gps_nmea_output_enabled;
 extern bool bmp280_enabled;
 extern bool si5351_enabled;
+extern bool pulse_counter_enabled;
 
 extern volatile bool system_initialized;
 

src/drivers/pulse_counter/pulse_counter.c

@@ -0,0 +1,55 @@
+#include "pulse_counter.h"
+#include "stm32f10x_exti.h"
+#include "stm32f10x_gpio.h"
+#include "stm32f10x.h"
+#include "misc.h"
+#include "config.h"
+
+// The pulse count will wrap to zero at 65535 as it is stored as a 16-bit unsigned integer value
+uint16_t pulse_count = 0;
+
+void pulse_counter_init(int pin_mode, int edge)
+{
+    // Initialize pin PB11 with optional internal pull-up resistor
+    GPIO_InitTypeDef gpio_init;
+    gpio_init.GPIO_Pin = GPIO_Pin_11;
+    gpio_init.GPIO_Mode = (pin_mode == PULSE_COUNTER_PIN_MODE_INTERNAL_PULL_UP)
+                          ? GPIO_Mode_IPU :
+                          ((pin_mode == PULSE_COUNTER_PIN_MODE_INTERNAL_PULL_DOWN)
+                           ? GPIO_Mode_IPD
+                           : GPIO_Mode_IN_FLOATING);
+    gpio_init.GPIO_Speed = GPIO_Speed_10MHz;
+    GPIO_Init(GPIOB, &gpio_init);
+
+    // PB11 is connected to interrupt line 11, set trigger on the configured edge and enable the interrupt
+    EXTI_InitTypeDef exti_init;
+    exti_init.EXTI_Line = EXTI_Line11;
+    exti_init.EXTI_Mode = EXTI_Mode_Interrupt;
+    exti_init.EXTI_Trigger = (edge == PULSE_COUNTER_INTERRUPT_EDGE_FALLING)
+                             ? EXTI_Trigger_Falling
+                             : EXTI_Trigger_Rising;
+    exti_init.EXTI_LineCmd = ENABLE;
+    EXTI_Init(&exti_init);
+
+    // Attach interrupt line to port B
+    GPIO_EXTILineConfig(GPIO_PortSourceGPIOB, GPIO_PinSource11);
+
+    // PB11 is connected to EXTI_Line11, which has EXTI15_10_IRQn vector. Use priority 0 for now.
+    NVIC_InitTypeDef NVIC_InitStruct;
+    NVIC_InitStruct.NVIC_IRQChannel = EXTI15_10_IRQn;
+    NVIC_InitStruct.NVIC_IRQChannelPreemptionPriority = 0x00;
+    NVIC_InitStruct.NVIC_IRQChannelSubPriority = 0x00;
+    NVIC_InitStruct.NVIC_IRQChannelCmd = ENABLE;
+    NVIC_Init(&NVIC_InitStruct);
+}
+
+uint16_t pulse_counter_get_count()
+{
+    return pulse_count;
+}
+
+void EXTI15_10_IRQHandler(void)
+{
+    pulse_count = pulse_count + 1;
+    EXTI_ClearITPendingBit(EXTI_Line11);
+}

src/drivers/pulse_counter/pulse_counter.h

@@ -0,0 +1,5 @@
+#include <stdint.h>
+#include <stdbool.h>
+
+void pulse_counter_init(int pin_mode, int edge);
+uint16_t pulse_counter_get_count();

src/hal/stm_lib/inc/stm32f10x_exti.h

@@ -0,0 +1,199 @@
+/**
+  ******************************************************************************
+  * @file    stm32f10x_exti.h
+  * @author  MCD Application Team
+  * @version V3.6.1
+  * @date    05-March-2012
+  * @brief   This file contains all the functions prototypes for the EXTI firmware
+  *          library.
+ *******************************************************************************
+ * Copyright (c) 2014, STMicroelectronics
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. Neither the name of STMicroelectronics nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *******************************************************************************
+ */
+
+/* Define to prevent recursive inclusion -------------------------------------*/
+#ifndef __STM32F10x_EXTI_H
+#define __STM32F10x_EXTI_H
+
+#ifdef __cplusplus
+ extern "C" {
+#endif
+
+/* Includes ------------------------------------------------------------------*/
+#include "stm32f10x.h"
+
+/** @addtogroup STM32F10x_StdPeriph_Driver
+  * @{
+  */
+
+/** @addtogroup EXTI
+  * @{
+  */
+
+/** @defgroup EXTI_Exported_Types
+  * @{
+  */
+
+/** 
+  * @brief  EXTI mode enumeration  
+  */
+
+typedef enum
+{
+  EXTI_Mode_Interrupt = 0x00,
+  EXTI_Mode_Event = 0x04
+}EXTIMode_TypeDef;
+
+#define IS_EXTI_MODE(MODE) (((MODE) == EXTI_Mode_Interrupt) || ((MODE) == EXTI_Mode_Event))
+
+/** 
+  * @brief  EXTI Trigger enumeration  
+  */
+
+typedef enum
+{
+  EXTI_Trigger_Rising = 0x08,
+  EXTI_Trigger_Falling = 0x0C,  
+  EXTI_Trigger_Rising_Falling = 0x10
+}EXTITrigger_TypeDef;
+
+#define IS_EXTI_TRIGGER(TRIGGER) (((TRIGGER) == EXTI_Trigger_Rising) || \
+                                  ((TRIGGER) == EXTI_Trigger_Falling) || \
+                                  ((TRIGGER) == EXTI_Trigger_Rising_Falling))
+/** 
+  * @brief  EXTI Init Structure definition  
+  */
+
+typedef struct
+{
+  uint32_t EXTI_Line;               /*!< Specifies the EXTI lines to be enabled or disabled.
+                                         This parameter can be any combination of @ref EXTI_Lines */
+   
+  EXTIMode_TypeDef EXTI_Mode;       /*!< Specifies the mode for the EXTI lines.
+                                         This parameter can be a value of @ref EXTIMode_TypeDef */
+
+  EXTITrigger_TypeDef EXTI_Trigger; /*!< Specifies the trigger signal active edge for the EXTI lines.
+                                         This parameter can be a value of @ref EXTITrigger_TypeDef */
+
+  FunctionalState EXTI_LineCmd;     /*!< Specifies the new state of the selected EXTI lines.
+                                         This parameter can be set either to ENABLE or DISABLE */ 
+}EXTI_InitTypeDef;
+
+/**
+  * @}
+  */
+
+/** @defgroup EXTI_Exported_Constants
+  * @{
+  */
+
+/** @defgroup EXTI_Lines 
+  * @{
+  */
+
+#define EXTI_Line0       ((uint32_t)0x00001)  /*!< External interrupt line 0 */
+#define EXTI_Line1       ((uint32_t)0x00002)  /*!< External interrupt line 1 */
+#define EXTI_Line2       ((uint32_t)0x00004)  /*!< External interrupt line 2 */
+#define EXTI_Line3       ((uint32_t)0x00008)  /*!< External interrupt line 3 */
+#define EXTI_Line4       ((uint32_t)0x00010)  /*!< External interrupt line 4 */
+#define EXTI_Line5       ((uint32_t)0x00020)  /*!< External interrupt line 5 */
+#define EXTI_Line6       ((uint32_t)0x00040)  /*!< External interrupt line 6 */
+#define EXTI_Line7       ((uint32_t)0x00080)  /*!< External interrupt line 7 */
+#define EXTI_Line8       ((uint32_t)0x00100)  /*!< External interrupt line 8 */
+#define EXTI_Line9       ((uint32_t)0x00200)  /*!< External interrupt line 9 */
+#define EXTI_Line10      ((uint32_t)0x00400)  /*!< External interrupt line 10 */
+#define EXTI_Line11      ((uint32_t)0x00800)  /*!< External interrupt line 11 */
+#define EXTI_Line12      ((uint32_t)0x01000)  /*!< External interrupt line 12 */
+#define EXTI_Line13      ((uint32_t)0x02000)  /*!< External interrupt line 13 */
+#define EXTI_Line14      ((uint32_t)0x04000)  /*!< External interrupt line 14 */
+#define EXTI_Line15      ((uint32_t)0x08000)  /*!< External interrupt line 15 */
+#define EXTI_Line16      ((uint32_t)0x10000)  /*!< External interrupt line 16 Connected to the PVD Output */
+#define EXTI_Line17      ((uint32_t)0x20000)  /*!< External interrupt line 17 Connected to the RTC Alarm event */
+#define EXTI_Line18      ((uint32_t)0x40000)  /*!< External interrupt line 18 Connected to the USB Device/USB OTG FS
+                                                   Wakeup from suspend event */                                    
+#define EXTI_Line19      ((uint32_t)0x80000)  /*!< External interrupt line 19 Connected to the Ethernet Wakeup event */
+                                          
+#define IS_EXTI_LINE(LINE) ((((LINE) & (uint32_t)0xFFF00000) == 0x00) && ((LINE) != (uint16_t)0x00))
+#define IS_GET_EXTI_LINE(LINE) (((LINE) == EXTI_Line0) || ((LINE) == EXTI_Line1) || \
+                            ((LINE) == EXTI_Line2) || ((LINE) == EXTI_Line3) || \
+                            ((LINE) == EXTI_Line4) || ((LINE) == EXTI_Line5) || \
+                            ((LINE) == EXTI_Line6) || ((LINE) == EXTI_Line7) || \
+                            ((LINE) == EXTI_Line8) || ((LINE) == EXTI_Line9) || \
+                            ((LINE) == EXTI_Line10) || ((LINE) == EXTI_Line11) || \
+                            ((LINE) == EXTI_Line12) || ((LINE) == EXTI_Line13) || \
+                            ((LINE) == EXTI_Line14) || ((LINE) == EXTI_Line15) || \
+                            ((LINE) == EXTI_Line16) || ((LINE) == EXTI_Line17) || \
+                            ((LINE) == EXTI_Line18) || ((LINE) == EXTI_Line19))
+
+                    
+/**
+  * @}
+  */
+
+/**
+  * @}
+  */
+
+/** @defgroup EXTI_Exported_Macros
+  * @{
+  */
+
+/**
+  * @}
+  */
+
+/** @defgroup EXTI_Exported_Functions
+  * @{
+  */
+
+void EXTI_DeInit(void);
+void EXTI_Init(EXTI_InitTypeDef* EXTI_InitStruct);
+void EXTI_StructInit(EXTI_InitTypeDef* EXTI_InitStruct);
+void EXTI_GenerateSWInterrupt(uint32_t EXTI_Line);
+FlagStatus EXTI_GetFlagStatus(uint32_t EXTI_Line);
+void EXTI_ClearFlag(uint32_t EXTI_Line);
+ITStatus EXTI_GetITStatus(uint32_t EXTI_Line);
+void EXTI_ClearITPendingBit(uint32_t EXTI_Line);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __STM32F10x_EXTI_H */
+/**
+  * @}
+  */
+
+/**
+  * @}
+  */
+
+/**
+  * @}
+  */
+
+/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/

src/hal/stm_lib/src/stm32f10x_exti.c

@@ -0,0 +1,284 @@
+/**
+  ******************************************************************************
+  * @file    stm32f10x_exti.c
+  * @author  MCD Application Team
+  * @version V3.6.1
+  * @date    05-March-2012
+  * @brief   This file provides all the EXTI firmware functions.
+ *******************************************************************************
+ * Copyright (c) 2014, STMicroelectronics
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. Neither the name of STMicroelectronics nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *******************************************************************************
+ */
+
+/* Includes ------------------------------------------------------------------*/
+#include "stm32f10x_exti.h"
+
+/** @addtogroup STM32F10x_StdPeriph_Driver
+  * @{
+  */
+
+/** @defgroup EXTI 
+  * @brief EXTI driver modules
+  * @{
+  */
+
+/** @defgroup EXTI_Private_TypesDefinitions
+  * @{
+  */
+
+/**
+  * @}
+  */
+
+/** @defgroup EXTI_Private_Defines
+  * @{
+  */
+
+#define EXTI_LINENONE    ((uint32_t)0x00000)  /* No interrupt selected */
+
+/**
+  * @}
+  */
+
+/** @defgroup EXTI_Private_Macros
+  * @{
+  */
+
+/**
+  * @}
+  */
+
+/** @defgroup EXTI_Private_Variables
+  * @{
+  */
+
+/**
+  * @}
+  */
+
+/** @defgroup EXTI_Private_FunctionPrototypes
+  * @{
+  */
+
+/**
+  * @}
+  */
+
+/** @defgroup EXTI_Private_Functions
+  * @{
+  */
+
+/**
+  * @brief  Deinitializes the EXTI peripheral registers to their default reset values.
+  * @param  None
+  * @retval None
+  */
+void EXTI_DeInit(void)
+{
+  EXTI->IMR = 0x00000000;
+  EXTI->EMR = 0x00000000;
+  EXTI->RTSR = 0x00000000; 
+  EXTI->FTSR = 0x00000000; 
+  EXTI->PR = 0x000FFFFF;
+}
+
+/**
+  * @brief  Initializes the EXTI peripheral according to the specified
+  *         parameters in the EXTI_InitStruct.
+  * @param  EXTI_InitStruct: pointer to a EXTI_InitTypeDef structure
+  *         that contains the configuration information for the EXTI peripheral.
+  * @retval None
+  */
+void EXTI_Init(EXTI_InitTypeDef* EXTI_InitStruct)
+{
+  uint32_t tmp = 0;
+
+  /* Check the parameters */
+  assert_param(IS_EXTI_MODE(EXTI_InitStruct->EXTI_Mode));
+  assert_param(IS_EXTI_TRIGGER(EXTI_InitStruct->EXTI_Trigger));
+  assert_param(IS_EXTI_LINE(EXTI_InitStruct->EXTI_Line));  
+  assert_param(IS_FUNCTIONAL_STATE(EXTI_InitStruct->EXTI_LineCmd));
+
+  tmp = (uint32_t)EXTI_BASE;
+     
+  if (EXTI_InitStruct->EXTI_LineCmd != DISABLE)
+  {
+    /* Clear EXTI line configuration */
+    EXTI->IMR &= ~EXTI_InitStruct->EXTI_Line;
+    EXTI->EMR &= ~EXTI_InitStruct->EXTI_Line;
+    
+    tmp += EXTI_InitStruct->EXTI_Mode;
+
+    *(__IO uint32_t *) tmp |= EXTI_InitStruct->EXTI_Line;
+
+    /* Clear Rising Falling edge configuration */
+    EXTI->RTSR &= ~EXTI_InitStruct->EXTI_Line;
+    EXTI->FTSR &= ~EXTI_InitStruct->EXTI_Line;
+    
+    /* Select the trigger for the selected external interrupts */
+    if (EXTI_InitStruct->EXTI_Trigger == EXTI_Trigger_Rising_Falling)
+    {
+      /* Rising Falling edge */
+      EXTI->RTSR |= EXTI_InitStruct->EXTI_Line;
+      EXTI->FTSR |= EXTI_InitStruct->EXTI_Line;
+    }
+    else
+    {
+      tmp = (uint32_t)EXTI_BASE;
+      tmp += EXTI_InitStruct->EXTI_Trigger;
+
+      *(__IO uint32_t *) tmp |= EXTI_InitStruct->EXTI_Line;
+    }
+  }
+  else
+  {
+    tmp += EXTI_InitStruct->EXTI_Mode;
+
+    /* Disable the selected external lines */
+    *(__IO uint32_t *) tmp &= ~EXTI_InitStruct->EXTI_Line;
+  }
+}
+
+/**
+  * @brief  Fills each EXTI_InitStruct member with its reset value.
+  * @param  EXTI_InitStruct: pointer to a EXTI_InitTypeDef structure which will
+  *         be initialized.
+  * @retval None
+  */
+void EXTI_StructInit(EXTI_InitTypeDef* EXTI_InitStruct)
+{
+  EXTI_InitStruct->EXTI_Line = EXTI_LINENONE;
+  EXTI_InitStruct->EXTI_Mode = EXTI_Mode_Interrupt;
+  EXTI_InitStruct->EXTI_Trigger = EXTI_Trigger_Falling;
+  EXTI_InitStruct->EXTI_LineCmd = DISABLE;
+}
+
+/**
+  * @brief  Generates a Software interrupt.
+  * @param  EXTI_Line: specifies the EXTI lines to be enabled or disabled.
+  *   This parameter can be any combination of EXTI_Linex where x can be (0..19).
+  * @retval None
+  */
+void EXTI_GenerateSWInterrupt(uint32_t EXTI_Line)
+{
+  /* Check the parameters */
+  assert_param(IS_EXTI_LINE(EXTI_Line));
+  
+  EXTI->SWIER |= EXTI_Line;
+}
+
+/**
+  * @brief  Checks whether the specified EXTI line flag is set or not.
+  * @param  EXTI_Line: specifies the EXTI line flag to check.
+  *   This parameter can be:
+  *     @arg EXTI_Linex: External interrupt line x where x(0..19)
+  * @retval The new state of EXTI_Line (SET or RESET).
+  */
+FlagStatus EXTI_GetFlagStatus(uint32_t EXTI_Line)
+{
+  FlagStatus bitstatus = RESET;
+  /* Check the parameters */
+  assert_param(IS_GET_EXTI_LINE(EXTI_Line));
+  
+  if ((EXTI->PR & EXTI_Line) != (uint32_t)RESET)
+  {
+    bitstatus = SET;
+  }
+  else
+  {
+    bitstatus = RESET;
+  }
+  return bitstatus;
+}
+
+/**
+  * @brief  Clears the EXTI's line pending flags.
+  * @param  EXTI_Line: specifies the EXTI lines flags to clear.
+  *   This parameter can be any combination of EXTI_Linex where x can be (0..19).
+  * @retval None
+  */
+void EXTI_ClearFlag(uint32_t EXTI_Line)
+{
+  /* Check the parameters */
+  assert_param(IS_EXTI_LINE(EXTI_Line));
+  
+  EXTI->PR = EXTI_Line;
+}
+
+/**
+  * @brief  Checks whether the specified EXTI line is asserted or not.
+  * @param  EXTI_Line: specifies the EXTI line to check.
+  *   This parameter can be:
+  *     @arg EXTI_Linex: External interrupt line x where x(0..19)
+  * @retval The new state of EXTI_Line (SET or RESET).
+  */
+ITStatus EXTI_GetITStatus(uint32_t EXTI_Line)
+{
+  ITStatus bitstatus = RESET;
+  uint32_t enablestatus = 0;
+  /* Check the parameters */
+  assert_param(IS_GET_EXTI_LINE(EXTI_Line));
+  
+  enablestatus =  EXTI->IMR & EXTI_Line;
+  if (((EXTI->PR & EXTI_Line) != (uint32_t)RESET) && (enablestatus != (uint32_t)RESET))
+  {
+    bitstatus = SET;
+  }
+  else
+  {
+    bitstatus = RESET;
+  }
+  return bitstatus;
+}
+
+/**
+  * @brief  Clears the EXTI's line pending bits.
+  * @param  EXTI_Line: specifies the EXTI lines to clear.
+  *   This parameter can be any combination of EXTI_Linex where x can be (0..19).
+  * @retval None
+  */
+void EXTI_ClearITPendingBit(uint32_t EXTI_Line)
+{
+  /* Check the parameters */
+  assert_param(IS_EXTI_LINE(EXTI_Line));
+  
+  EXTI->PR = EXTI_Line;
+}
+
+/**
+  * @}
+  */
+
+/**
+  * @}
+  */
+
+/**
+  * @}
+  */
+
+/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/

src/main.c

@@ -7,6 +7,7 @@
 #include "hal/datatimer.h"
 #include "drivers/ubxg6010/ubxg6010.h"
 #include "drivers/si4032/si4032.h"
+#include "drivers/pulse_counter/pulse_counter.h"
 #include "bmp280_handler.h"
 #include "si5351_handler.h"
 #include "radio.h"
@@ -33,7 +34,7 @@ void handle_timer_tick()
 
     if (leds_enabled) {
         // Blink fast until GPS fix is acquired
-        if (counter % (SYSTEM_SCHEDULER_TIMER_TICKS_PER_SECOND / 4) == 0)  {
+        if (counter % (SYSTEM_SCHEDULER_TIMER_TICKS_PER_SECOND / 4) == 0) {
             if (GPS_HAS_FIX(current_gps_data)) {
                 if (counter == 0) {
                     led_state = !led_state;
@@ -83,14 +84,18 @@ int main(void)
     if (gps_nmea_output_enabled) {
         log_info("External USART init\n");
         usart_ext_init(EXTERNAL_SERIAL_PORT_BAUD_RATE);
+    } else if (pulse_counter_enabled) {
+        log_info("Pulse counter init\n");
+        pulse_counter_init(PULSE_COUNTER_PIN_MODE, PULSE_COUNTER_INTERRUPT_EDGE);
     } else {
         log_info("I2C init: clock speed %d kHz\n", I2C_BUS_CLOCK_SPEED / 1000);
         i2c_init(I2C_BUS_CLOCK_SPEED);
     }
+
     log_info("SPI init\n");
     spi_init();
 
-gps_init:
+    gps_init:
     log_info("GPS init\n");
     success = ubxg6010_init();
     if (!success) {

src/telemetry.c

@@ -2,6 +2,7 @@
 #include "hal/system.h"
 #include "drivers/si4032/si4032.h"
 #include "drivers/ubxg6010/ubxg6010.h"
+#include "drivers/pulse_counter/pulse_counter.h"
 #include "bmp280_handler.h"
 #include "locator.h"
 #include "config.h"
@@ -19,6 +20,10 @@ void telemetry_collect(telemetry_data *data)
         bmp280_read_telemetry(data);
     }
 
+    if (pulse_counter_enabled) {
+        data->pulse_count = pulse_counter_get_count();
+    }
+
     ubxg6010_get_current_gps_data(&data->gps);
 
     // Zero out position data if we don't have a valid GPS fix.

src/telemetry.h

@@ -15,6 +15,7 @@ typedef struct _telemetry_data {
     int32_t temperature_celsius_100;
     uint32_t pressure_mbar_100;
     uint32_t humidity_percentage_100;
+    uint16_t pulse_count;
 
     gps_data gps;
 

src/template.c

@@ -89,7 +89,8 @@ size_t template_replace(char *dest, size_t dest_len, char *src, telemetry_data *
     strlcpy(temp, dest, dest_len);
     str_replace(dest, dest_len, temp, "$alt", replacement);
 
-    snprintf(replacement, sizeof(replacement), "%d", (int) ((float) data->gps.ground_speed_cm_per_second * 3.6f / 100.0f));
+    snprintf(replacement, sizeof(replacement), "%d",
+            (int) ((float) data->gps.ground_speed_cm_per_second * 3.6f / 100.0f));
     strlcpy(temp, dest, dest_len);
     str_replace(dest, dest_len, temp, "$gs", replacement);
 
@@ -101,6 +102,10 @@ size_t template_replace(char *dest, size_t dest_len, char *src, telemetry_data *
     strlcpy(temp, dest, dest_len);
     size_t len = str_replace(dest, dest_len, temp, "$he", replacement);
 
+    snprintf(replacement, sizeof(replacement), "%d", (int) data->pulse_count);
+    strlcpy(temp, dest, dest_len);
+    str_replace(dest, dest_len, temp, "$pc", replacement);
+
     free(temp);
 
     return len;

tests/CMakeLists.txt

@@ -7,7 +7,7 @@ project(RS41ng_test C CXX)
 
 set(BINARY ${CMAKE_PROJECT_NAME})
 
-file(GLOB_RECURSE USER_SOURCES "../src/codecs/*.c" "../src/template.c" "../src/utils.c")
+file(GLOB_RECURSE USER_SOURCES "../src/config.c" "../src/codecs/*.c" "../src/template.c" "../src/utils.c")
 file(GLOB_RECURSE USER_SOURCES_CXX "../src/codecs/*.cpp")
 file(GLOB_RECURSE USER_HEADERS "../src/codecs/*.h" "../src/template.h" "../src/utils.h" "../src/config.h")