rfm95.h

#pragma once

#include <stdbool.h>

#if (defined STM32L011xx) || (defined STM32L021xx) || \
	(defined STM32L031xx) || (defined STM32L041xx) || \
	(defined STM32L051xx) || (defined STM32L052xx) || (defined STM32L053xx) || \
	(defined STM32L061xx) || (defined STM32L062xx) || (defined STM32L063xx) || \
	(defined STM32L071xx) || (defined STM32L072xx) || (defined STM32L073xx) || \
	(defined STM32L081xx) || (defined STM32L082xx) || (defined STM32L083xx)
#include "stm32l0xx_hal.h"
#elif defined (STM32L412xx) || defined (STM32L422xx) || \
	defined (STM32L431xx) || (defined STM32L432xx) || defined (STM32L433xx) || defined (STM32L442xx) || defined (STM32L443xx) || \
	defined (STM32L451xx) || defined (STM32L452xx) || defined (STM32L462xx) || \
	defined (STM32L471xx) || defined (STM32L475xx) || defined (STM32L476xx) || defined (STM32L485xx) || defined (STM32L486xx) || \
    defined (STM32L496xx) || defined (STM32L4A6xx) || \
    defined (STM32L4R5xx) || defined (STM32L4R7xx) || defined (STM32L4R9xx) || defined (STM32L4S5xx) || defined (STM32L4S7xx) || defined (STM32L4S9xx)
#include "stm32l4xx_hal.h"
#elif defined (STM32F405xx) || defined (STM32F415xx) || defined (STM32F407xx) || defined (STM32F417xx) || \
    defined (STM32F427xx) || defined (STM32F437xx) || defined (STM32F429xx) || defined (STM32F439xx) || \
    defined (STM32F401xC) || defined (STM32F401xE) || defined (STM32F410Tx) || defined (STM32F410Cx) || \
    defined (STM32F410Rx) || defined (STM32F411xE) || defined (STM32F446xx) || defined (STM32F469xx) || \
    defined (STM32F479xx) || defined (STM32F412Cx) || defined (STM32F412Rx) || defined (STM32F412Vx) || \
    defined (STM32F412Zx) || defined (STM32F413xx) || defined (STM32F423xx)
#include "stm32f4xx_hal.h"
#elif defined (TESTING)
#include "testing/mock_hal.h"
#else
#error Platform not implemented
#endif

#ifndef RFM95_SPI_TIMEOUT
#define RFM95_SPI_TIMEOUT 10
#endif

#ifndef RFM95_WAKEUP_TIMEOUT
#define RFM95_WAKEUP_TIMEOUT 10
#endif

#ifndef RFM95_SEND_TIMEOUT
#define RFM95_SEND_TIMEOUT 100
#endif

#ifndef RFM95_RECEIVE_TIMEOUT
#define RFM95_RECEIVE_TIMEOUT 1000
#endif

#define RFM95_EEPROM_CONFIG_MAGIC 0xab67

typedef struct {

	uint32_t frequency;

} rfm95_channel_config_t;

typedef struct {

	/**
	 * MAGIC
	 */
	uint16_t magic;

	/**
	 * The current RX frame counter value.
	 */
	uint16_t rx_frame_count;

	/**
	 * The current TX frame counter value.
	 */
	uint16_t tx_frame_count;

	/**
	 * The delay to the RX1 window.
	 */
	uint8_t rx1_delay;

	/**
	 * The configuration of channels;
	 */
	rfm95_channel_config_t channels[16];

	/**
	 * Mask defining which channels are configured.
	 */
	uint16_t channel_mask;

} rfm95_eeprom_config_t;

typedef void (*rfm95_on_after_interrupts_configured)();

typedef bool (*rfm95_load_eeprom_config)(rfm95_eeprom_config_t *config);
typedef void (*rfm95_save_eeprom_config)(const rfm95_eeprom_config_t *config);

typedef uint32_t (*rfm95_get_precision_tick)();
typedef void (*rfm95_precision_sleep_until)(uint32_t ticks_target);

typedef uint8_t (*rfm95_random_int)(uint8_t max);
typedef uint8_t (*rfm95_get_battery_level)();

typedef enum
{
	RFM95_INTERRUPT_DIO0,
	RFM95_INTERRUPT_DIO1,
	RFM95_INTERRUPT_DIO5

} rfm95_interrupt_t;

typedef enum
{
	RFM95_RECEIVE_MODE_NONE,
	RFM95_RECEIVE_MODE_RX1_ONLY,
	RFM95_RECEIVE_MODE_RX12,
} rfm95_receive_mode_t;

#define RFM95_INTERRUPT_COUNT 3

/**
 * Structure defining a handle describing an RFM95(W) transceiver.
 */
typedef struct {

	/**
	 * The handle to the SPI bus for the device.
	 */
	SPI_HandleTypeDef *spi_handle;

	/**
	 * The port of the NSS pin.
	 */
	GPIO_TypeDef *nss_port;

	/**
	 * The NSS pin.
	 */
	uint16_t nss_pin;

	/**
	 * The port of the RST pin.
	 */
	GPIO_TypeDef *nrst_port;

	/**
	 * The RST pin.
	 */
	uint16_t nrst_pin;

	/**
	 * The device address for the LoraWAN
	 */
	uint8_t device_address[4];

	/**
	 * The network session key for ABP activation with the LoraWAN
	 */
	uint8_t network_session_key[16];

	/**
	 * The application session key for ABP activation with the LoraWAN
	 */
	uint8_t application_session_key[16];

	/**
	 * The frequency of the precision tick in Hz.
	 */
	uint32_t precision_tick_frequency;

	/**
	 * The +/- timing drift per second in nanoseconds.
	 */
	uint32_t precision_tick_drift_ns_per_s;

	/**
	 * The receive mode to operate at.
	 */
	rfm95_receive_mode_t receive_mode;

	/**
	 * Function provided that returns a precise tick for timing critical operations.
	 */
	rfm95_get_precision_tick get_precision_tick;

	/**
	 * Function that provides a precise sleep until a given tick count is reached.
	 */
	rfm95_precision_sleep_until precision_sleep_until;

	/**
	 * Function that provides a random integer.
	 */
	rfm95_random_int random_int;

	/**
	 * Function that returns the device's battery level.
	 */
	rfm95_get_battery_level get_battery_level;

	/**
	 * The load config function pointer can be used to load config values from non-volatile memory.
	 * Can be set to NULL to skip.
	 */
	rfm95_load_eeprom_config reload_config;

	/**
	 * The save config function pointer can be used to store config values in non-volatile memory.
	 * Can be set to NULL to skip.
	 */
	rfm95_save_eeprom_config save_config;

	/**
	 * Callback called after the interrupt functions have been properly configred;
	 */
	rfm95_on_after_interrupts_configured on_after_interrupts_configured;

	/**
	 * The config saved into the eeprom.
	 */
	rfm95_eeprom_config_t config;

	/**
	 * Tick values when each interrupt was called.
	 */
	volatile uint32_t interrupt_times[RFM95_INTERRUPT_COUNT];

} rfm95_handle_t;

bool rfm95_init(rfm95_handle_t *handle);

bool rfm95_set_power(rfm95_handle_t *handle, int8_t power);

bool rfm95_send_receive_cycle(rfm95_handle_t *handle, const uint8_t *send_data, size_t send_data_length);

void rfm95_on_interrupt(rfm95_handle_t *handle, rfm95_interrupt_t interrupt);