/******************************************************************************* * * ttn-esp32 - The Things Network device library for ESP-IDF / SX127x * * Copyright (c) 2018-2021 Manuel Bleichenbacher * * Licensed under MIT License * https://opensource.org/licenses/MIT * * High-level C API for ttn-esp32. *******************************************************************************/ /** * @defgroup c_api C API */ #ifndef TTN_C_H #define TTN_C_H #include "driver/spi_master.h" #include #ifdef __cplusplus extern "C" { #endif /** * @addtogroup c_api * * @{ */ /** * @brief Constant for indicating that a pin is not connected */ #define TTN_NOT_CONNECTED 0xff /** * @brief Integer data type for specifiying the port of an uplink or downlink message. */ typedef uint8_t ttn_port_t; /** * @brief Response codes */ typedef enum { /** @brief Transmission failed error */ TTN_ERROR_TRANSMISSION_FAILED = -1, /** @brief Unexpected or internal error */ TTN_ERROR_UNEXPECTED = -10, /** @brief Successful transmission of an uplink message */ TTN_SUCCESSFUL_TRANSMISSION = 1, /** @brief Successful receipt of a downlink message */ TTN_SUCCESSFUL_RECEIVE = 2 } ttn_response_code_t; /** * @brief RX/TX window */ typedef enum { /** * @brief Outside RX/TX window */ TTN_WINDOW_IDLE = 0, /** * @brief Transmission window (up to RX1 window) */ TTN_WINDOW_TX = 1, /** * @brief Reception window 1 (up to RX2 window) */ TTN_WINDOW_RX1 = 2, /** * @brief Reception window 2 */ TTN_WINDOW_RX2 = 3 } ttn_rx_tx_window_t; /** * @brief Spreading Factor */ typedef enum { /** * @brief Unused / undefined spreading factor */ TTN_SF_NONE = 0, /** * @brief Frequency Shift Keying (FSK) */ TTN_FSK = 1, /** * @brief Spreading Factor 7 (SF7) */ TTN_SF7 = 2, /** * @brief Spreading Factor 8 (SF8) */ TTN_SF8 = 3, /** * @brief Spreading Factor 9 (SF9) */ TTN_SF9 = 4, /** * @brief Spreading Factor 10 (SF10) */ TTN_SF10 = 5, /** * @brief Spreading Factor 11 (SF11) */ TTN_SF11 = 6, /** * @brief Spreading Factor 12 (SF12) */ TTN_SF12 = 7 } ttn_spreading_factor_t; /** * @brief Bandwidth */ typedef enum { /** * @brief Undefined/unused bandwidth */ TTN_BW_NONE = 0, /** * @brief Bandwidth of 125 kHz */ TTN_BW_125 = 1, /** * @brief Bandwidth of 250 kHz */ TTN_BW_250 = 2, /** * @brief Bandwidth of 500 kHz */ TTN_BW_500 = 3 } ttn_bandwidth_t; /** * @brief Data Rate * * Note that the spreading factor, bandwidth, bit rate and maximum message * size associated with each data rate depends on the region. */ typedef enum { /** * @brief Data rate for region AS923 using SF12 and 125 kHz bandwidth. */ TTN_DR_AS923_SF12 = 0, /** * @brief Data rate for region AS923 using SF11 and 125 kHz bandwidth. */ TTN_DR_AS923_SF11 = 1, /** * @brief Data rate for region AS923 using SF10 and 125 kHz bandwidth. */ TTN_DR_AS923_SF10 = 2, /** * @brief Data rate for region AS923 using SF9 and 125 kHz bandwidth. */ TTN_DR_AS923_SF9 = 3, /** * @brief Data rate for region AS923 using SF8 and 125 kHz bandwidth. */ TTN_DR_AS923_SF8 = 4, /** * @brief Data rate for region AS923 using SF7 and 125 kHz bandwidth. */ TTN_DR_AS923_SF7_BW125 = 5, /** * @brief Data rate for region AS923 using SF7 and 250 kHz bandwidth. */ TTN_DR_AS923_SF7_BW250 = 6, /** * @brief Data rate for region AS923 using FSK and 50 kpbs. */ TTN_DR_AS923_FSK = 7, /** * @brief Data rate for region AU915 using SF12 and 125 kHz bandwidth. */ TTN_DR_AU915_SF12 = 0, /** * @brief Data rate for region AU915 using SF11 and 125 kHz bandwidth. */ TTN_DR_AU915_SF11 = 1, /** * @brief Data rate for region AU915 using SF10 and 125 kHz bandwidth. */ TTN_DR_AU915_SF10 = 2, /** * @brief Data rate for region AU915 using SF9 and 125 kHz bandwidth. */ TTN_DR_AU915_SF9 = 3, /** * @brief Data rate for region AU915 using SF8 and 125 kHz bandwidth. */ TTN_DR_AU915_SF8 = 4, /** * @brief Data rate for region AU915 using SF7 and 125 kHz bandwidth. */ TTN_DR_AU915_SF7 = 5, /** * @brief Data rate for region AU915 using SF8 and 500 kHz bandwidth. */ TTN_DR_AU915_SF8_BW500 = 6, /** * @brief Data rate for region AU915 using SF12 and 500 kHz bandwidth. * * Reserved for future applications. */ TTN_DR_AU915_SF12_BW500 = 8, /** * @brief Data rate for region AU915 using SF11 and 500 kHz bandwidth. * * Reserved for future applications. */ TTN_DR_AU915_SF11_BW500 = 9, /** * @brief Data rate for region AU915 using SF10 and 500 kHz bandwidth. * * Reserved for future applications. */ TTN_DR_AU915_SF10_BW500 = 10, /** * @brief Data rate for region AU915 using SF9 and 500 kHz bandwidth. * * Reserved for future applications. */ TTN_DR_AU915_SF9_BW500 = 11, /** * @brief Data rate for region AU915 using SF8 and 500 kHz bandwidth. * * Reserved for future applications. */ TTN_DR_AU915_SF8_BW500_DR12 = 12, /** * @brief Data rate for region AU915 using SF7 and 500 kHz bandwidth. * * Reserved for future applications. */ TTN_DR_AU915_SF7_BW500 = 13, /** * @brief Data rate for region EU868 using SF12 and 125 kHz bandwidth. */ TTN_DR_EU868_SF12 = 0, /** * @brief Data rate for region EU868 using SF11 and 125 kHz bandwidth. */ TTN_DR_EU868_SF11 = 1, /** * @brief Data rate for region EU868 using SF10 and 125 kHz bandwidth. */ TTN_DR_EU868_SF10 = 2, /** * @brief Data rate for region EU868 using SF9 and 125 kHz bandwidth. */ TTN_DR_EU868_SF9 = 3, /** * @brief Data rate for region EU868 using SF8 and 125 kHz bandwidth. */ TTN_DR_EU868_SF8 = 4, /** * @brief Data rate for region EU868 using SF7 and 125 kHz bandwidth. */ TTN_DR_EU868_SF7_BW125 = 5, /** * @brief Data rate for region EU868 using SF7 and 250 kHz bandwidth. */ TTN_DR_EU868_SF7_BW250 = 6, /** * @brief Data rate for region EU868 using FSK and 50 kpbs. */ TTN_DR_EU868_FSK = 7, /** * @brief Data rate for region IN866 using SF12 and 125 kHz bandwidth. */ TTN_DR_IN866_SF12 = 0, /** * @brief Data rate for region IN866 using SF11 and 125 kHz bandwidth. */ TTN_DR_IN866_SF11 = 1, /** * @brief Data rate for region IN866 using SF10 and 125 kHz bandwidth. */ TTN_DR_IN866_SF10 = 2, /** * @brief Data rate for region IN866 using SF9 and 125 kHz bandwidth. */ TTN_DR_IN866_SF9 = 3, /** * @brief Data rate for region IN866 using SF8 and 125 kHz bandwidth. */ TTN_DR_IN866_SF8 = 4, /** * @brief Data rate for region IN866 using SF7 and 125 kHz bandwidth. */ TTN_DR_IN866_SF7 = 5, /** * @brief Data rate for region IN866 using FSK and 50 kpbs. */ TTN_DR_IN866_FSK = 7, /** * @brief Data rate for region KR920 using SF12 and 125 kHz bandwidth. */ TTN_DR_KR920_SF12 = 0, /** * @brief Data rate for region KR920 using SF11 and 125 kHz bandwidth. */ TTN_DR_KR920_SF11 = 1, /** * @brief Data rate for region KR920 using SF10 and 125 kHz bandwidth. */ TTN_DR_KR920_SF10 = 2, /** * @brief Data rate for region KR920 using SF9 and 125 kHz bandwidth. */ TTN_DR_KR920_SF9 = 3, /** * @brief Data rate for region KR920 using SF8 and 125 kHz bandwidth. */ TTN_DR_KR920_SF8 = 4, /** * @brief Data rate for region KR920 using SF7 and 125 kHz bandwidth. */ TTN_DR_KR920_SF7 = 5, /** * @brief Data rate for region US915 using SF10 and 125 kHz bandwidth. */ TTN_DR_US915_SF10 = 0, /** * @brief Data rate for region US915 using SF9 and 125 kHz bandwidth. */ TTN_DR_US915_SF9 = 1, /** * @brief Data rate for region US915 using SF8 and 125 kHz bandwidth. */ TTN_DR_US915_SF8 = 2, /** * @brief Data rate for region US915 using SF7 and 125 kHz bandwidth. */ TTN_DR_US915_SF7 = 3, /** * @brief Data rate for region US915 using SF8 and 500 kHz bandwidth. */ TTN_DR_US915_SF8_BW500 = 4, /** * @brief Data rate for region US915 using SF12 and 500 kHz bandwidth. * * Reserved for future applications. */ TTN_DR_US915_SF12_BW500 = 8, /** * @brief Data rate for region US915 using SF11 and 500 kHz bandwidth. * * Reserved for future applications. */ TTN_DR_US915_SF11_BW500 = 9, /** * @brief Data rate for region US915 using SF10 and 500 kHz bandwidth. * * Reserved for future applications. */ TTN_DR_US915_SF10_BW500 = 10, /** * @brief Data rate for region US915 using SF9 and 500 kHz bandwidth. * * Reserved for future applications. */ TTN_DR_US915_SF9_BW500 = 11, /** * @brief Data rate for region US915 using SF8 and 500 kHz bandwidth. * * Reserved for future applications. */ TTN_DR_US915_SF8_BW500_DR12 = 12, /** * @brief Data rate for region US915 using SF7 and 500 kHz bandwidth. * * Reserved for future applications. */ TTN_DR_US915_SF7_BW500 = 13, /** * @brief Default data rate for joining. */ TTN_DR_JOIN_DEFAULT = 255 } ttn_data_rate_t; /** * @brief RF settings for TX or RX */ typedef struct { /** * @brief Spreading Factor (SF) */ ttn_spreading_factor_t spreading_factor; /** * @brief Bandwidth (BW) */ ttn_bandwidth_t bandwidth; /** * @brief Frequency, in Hz */ uint32_t frequency; } ttn_rf_settings_t; /** * @brief Callback for recieved messages * * @param payload pointer to the received bytes * @param length number of received bytes * @param port port the message was received on */ typedef void (*ttn_message_cb)(const uint8_t *payload, size_t length, ttn_port_t port); /** * @brief Initializes The Things Network device instance. * * Call this function once at the start of the program and before all other TTN functions. */ void ttn_init(void); /** * @brief Configures the pins used to communicate with the LoRaWAN radio chip. * * Before calling this member function, the SPI bus needs to be configured using `spi_bus_initialize()`. * Additionally, `gpio_install_isr_service()` must have been called to initialize the GPIO ISR handler service. * * Call this function after @ref ttn_init() and before all other TTN functions. * * @param spi_host The SPI bus/peripherial to use (`SPI1_HOST`, `SPI2_HOST`, `SPI3_HOST`, `FSPI_HOST`, `HSPI_HOST`, or `VSPI_HOST`). * @param nss The GPIO pin number connected to the radio chip's NSS pin (serving as the SPI chip select) * @param rxtx The GPIO pin number connected to the radio chip's RXTX pin (@ref TTN_NOT_CONNECTED if not * connected) * @param rst The GPIO pin number connected to the radio chip's RST pin (@ref TTN_NOT_CONNECTED if not * connected) * @param dio0 The GPIO pin number connected to the radio chip's DIO0 pin * @param dio1 The GPIO pin number connected to the radio chip's DIO1 pin */ void ttn_configure_pins(spi_host_device_t spi_host, uint8_t nss, uint8_t rxtx, uint8_t rst, uint8_t dio0, uint8_t dio1); /** * @brief Sets the frequency sub-band to be used. * * For regions with sub-bands (USA, Australia), sets the sub-band to be used for uplink communication. * For other regions, this function has no effect. * * The sub-band must be set before joining or sending the first message. * * If not set, it defaults to sub-band 2 as defined by TTN. * * @param band band (0 for all bands, or value between 1 and 8) */ void ttn_set_subband(int band); /** * @brief Sets the keys needed to activate the device via OTAA, without activating it. * * The provided DevEUI, AppEUI/JoinEUI and AppKey are saved in non-volatile memory. Before * this function is called, `nvs_flash_init()` must have been called once. * * In order to reduce flash wear, this function detects if the keys have not changed * and will not write them again. * * Call @ref ttn_join() to activate the device. * * @param dev_eui DevEUI (16 character string with hexadecimal data) * @param app_eui AppEUI/JoinEUI of the device (16 character string with hexadecimal data) * @param app_key AppKey of the device (32 character string with hexadecimal data) * @return `true` if the provisioning was successful, `false` if the provisioning failed */ bool ttn_provision(const char *dev_eui, const char *app_eui, const char *app_key); /** * @brief Sets the keys needed to activate the device via OTAA, without activating it. * * The provided DevEUI, AppEUI/JoinEUI and AppKey are only stored in RAM and will be lost * when the device is powered off or put in deep sleep. * * Call @ref ttn_join() to activate the device. * * @param dev_eui DevEUI (16 character string with hexadecimal data) * @param app_eui AppEUI/JoinEUI of the device (16 character string with hexadecimal data) * @param app_key AppKey of the device (32 character string with hexadecimal data) * @return `true` if the provisioning was successful, `false` if the provisioning failed */ bool ttn_provision_transiently(const char *dev_eui, const char *app_eui, const char *app_key); /** * @brief Sets the information needed to activate the device via OTAA, using the MAC to generate the DevEUI * and without activating it. * * The generated DevEUI and the provided AppEUI/JoinEUI and AppKey are saved in non-volatile memory. Before * this function is called, `nvs_flash_init` must have been called once. * * In order to reduce flash wear, this function detects if the keys have not changed * and will not write them again. * * The DevEUI is generated by retrieving the ESP32's WiFi MAC address and expanding it into a DevEUI * by adding FFFE in the middle. So the MAC address A0:B1:C2:01:02:03 becomes the EUI A0B1C2FFFE010203. * This hexadecimal data can be entered into the DevEUI field in the TTN console. * * Generating the DevEUI from the MAC address allows to flash the same AppEUI/JoinEUI and AppKey to a batch of * devices. However, using the same AppKey for multiple devices is insecure. Only use this approach if * it is okay for that the LoRa communication of your application can easily be intercepted and that * forged data can be injected. * * Call @ref ttn_join() to activate. * * @param app_eui AppEUI/JoinEUI of the device (16 character string with hexadecimal data) * @param app_key AppKey of the device (32 character string with hexadecimal data) * @return `true` if the provisioning was successful, `false` if the provisioning failed */ bool ttn_provision_with_mac(const char *app_eui, const char *app_key); /** * @brief Starts task listening on configured UART for AT commands. * * Run `make menuconfig` to configure it. */ void ttn_start_provisioning_task(void); /** * @brief Waits until the DevEUI, AppEUI/JoinEUI and AppKey have been provisioned * by the provisioning task. * * If the device has already been provisioned (stored data in NVS, call of provision() * or call of @ref ttn_join_with_keys(), this function immediately returns. */ void ttn_wait_for_provisioning(void); /** * @brief Activates the device via OTAA using previously provisioned keys. * * The DevEUI, AppEUI/JoinEUI and AppKey must have already been provisioned by a call * to @ref ttn_provision() or @ref ttn_provision_with_mac(). * Before this function is called, `nvs_flash_init()` must have been called once. * * The RF module is initialized and the TTN background task is started. * * The function blocks until the activation has completed or failed. * * @return `true` if the activation was succesful, `false` if the activation failed */ bool ttn_join(void); /** * @brief Activates the device via OTAA using the provided keys. * * For the activation, the provided DevEUI, AppEUI/JoinEUI and AppKey are used. * They are NOT saved in non-volatile memory. * * The RF module is initialized and the TTN background task is started. * * The function blocks until the activation has completed or failed. * * @param dev_eui DevEUI (16 character string with hexadecimal data) * @param app_eui AppEUI/JoinEUI of the device (16 character string with hexadecimal data) * @param app_key AppKey of the device (32 character string with hexadecimal data) * @return `true` if the activation was succesful, `false` if the activation failed */ bool ttn_join_with_keys(const char *dev_eui, const char *app_eui, const char *app_key); /** * @brief Resumes TTN communication after deep sleep. * * The communcation state is restored from data previously saved in RTC memory. * The RF module and the TTN background task are started. * * This function is called instead of @ref ttn_join_with_keys() or @ref ttn_join() * to continue with the established communication and to avoid a further join procedure. * * @return `true` if the device was able to resume, `false` otherwise. */ bool ttn_resume_after_deep_sleep(void); /** * @brief Resumes TTN communication after power off. * * The communcation state is restored from data previously saved in NVS (non-volatile storage). * The RF module and the TTN background task are started. * * This function is called instead of @ref ttn_join_with_keys() or @ref ttn_join() * to continue with the established communication and to avoid a further join procedure. * * In order to advance the clock, the estimated duration the device was powered off has to * be specified. As the exact duration is probably not known, an estimation of the shortest * duration between power-off and next power-on can be used instead. * * If the device has access to the real time, set the system time (using `settimeofday()`) * before calling this function (and before @ref ttn_join()) and pass 0 for `off_duration`. * * Before this function is called, `nvs_flash_init()` must have been called once. * * @param off_duration duration the device was powered off (in minutes) * @return `true` if the device was able to resume, `false` otherwise. */ bool ttn_resume_after_power_off(int off_duration); /** * @brief Stops all activies and prepares for deep sleep. * * This function is called before entering deep sleep. It saves the current * communication state in RTC memory and shuts down the RF module and the * TTN background task. * * It neither clears the provisioned keys nor the configured pins * but they will be lost if the device goes into deep sleep. * * Before calling this function, use @ref ttn_busy_duration() to check * that the TTN device is idle and ready to go to deep sleep. * * To restart communication, @ref ttn_resume_after_deep_sleep() must be called. */ void ttn_prepare_for_deep_sleep(void); /** * @brief Stops all activies and prepares for power off. * * This function is called before powering off the device. It saves the current * communication state in NVS (non-volatile storage) and shuts down the RF module * and the TTN background task. * * It neither clears the provisioned keys nor the configured pins * but they will be lost if the device is powered off. * * Before calling this function, use @ref ttn_busy_duration() to check * that the TTN device is idle and ready to be powered off. * * To restart communication, @ref ttn_resume_after_power_off(int) must be called. * * Before this function is called, `nvs_flash_init()` must have been called once. */ void ttn_prepare_for_power_off(void); /** * @brief Waits until the TTN device is idle. * * If the TTN device is idle, the ESP32 can go into deep sleep mode * or be powered off without disrupting an on-going communication. */ void ttn_wait_for_idle(void); /** * @brief Returns the minimum duration the TTN device will be busy. * * This function can be called to check whether the TTN device is * still involved in communication or ready to go to deep sleep or * to be powered off. * * If it returns 0, the TTN communication is idle and the device can go * to deep sleep or can be powered off. * * If it returns a value different from 0, the value indicates the duration * the device will be certainly busy. After that time, this function must be * called again. It might still return a value different from 0. * * @return busy duration (in FreeRTOS ticks) */ TickType_t ttn_busy_duration(void); /** * @brief Stops all activies. * * This function shuts down the RF module and the TTN background task. It neither clears the * provisioned keys nor the configured pins. The currentat device state (and activation) * are lost. * * To restart communication, @ref ttn_join_with_keys() and @ref ttn_join() must be called. */ void ttn_shutdown(void); /** * @brief Transmits a message * * The function blocks until the message could be transmitted and a message has been received * in the subsequent receive window (or the window expires). Additionally, the function will * first wait until the duty cycle allows a transmission (enforcing the duty cycle limits). * * @param payload bytes to be transmitted * @param length number of bytes to be transmitted * @param port port (use 1 as default) * @param confirm flag indicating if a confirmation should be requested (use `false` as default) * @return @ref TTN_SUCCESSFUL_TRANSMISSION for successful transmission, @ref TTN_ERROR_TRANSMISSION_FAILED for * failed transmission, @ref TTN_ERROR_UNEXPECTED for unexpected error */ ttn_response_code_t ttn_transmit_message(const uint8_t *payload, size_t length, ttn_port_t port, bool confirm); /** * @brief Sets the function to be called when a message is received * * When a message is received, the specified function is called. The * message, its length and the port number are provided as * parameters. The values are only valid during the duration of the * callback. So they must be immediately processed or copied. * * Messages are received as a result of @ref ttn_transmit_message(). The callback is called * in the task that called this function and it occurs before this function * returns control to the caller. * * @param callback the callback function */ void ttn_on_message(ttn_message_cb callback); /** * @brief Checks if DevEUI, AppEUI/JoinEUI and AppKey have been stored in non-volatile storage * or have been provided by a call to @ref ttn_join_with_keys() or to @ref ttn_provision_transiently(). * * @return `true` if they are stored, complete and of the correct size, `false` otherwise */ bool ttn_is_provisioned(void); /** * @brief Sets the RSSI calibration value for LBT (Listen Before Talk). * * This value is added to RSSI measured prior to decision. It must include the guardband. * Ignored in US, EU, IN and other countries where LBT is not required. * Defaults to 10 dB. * * @param rssi_cal RSSI calibration value, in dB */ void ttn_set_rssi_cal(int8_t rssi_cal); /** * Returns whether Adaptive Data Rate (ADR) is enabled. * * @return `true` if enabled, `false` if disabled */ bool ttn_adr_enabled(void); /** * @brief Enables or disabled Adaptive Data Rate (ADR). * * ADR is enabled by default. It optimizes data rate, airtime and energy consumption * for devices with stable RF conditions. It should be turned off for mobile devices. * * @param enabled `true` to enable, `false` to disable */ void ttn_set_adr_enabled(bool enabled); /** * @brief Sets the transmission data rate (i.e. the data rate for uplink messages). * * If ADR is enabled, it's is used as the initial data rate and later adjusted depending * on the RF conditions. If ADR is disabled, it is used for all uplink messages. * * @param data_rate data rate (use constants of enum @ref ttn_data_rate_t) */ void ttn_set_data_rate(ttn_data_rate_t data_rate); /** * @brief Sets the maximum power for transmission * * The power is specified in dBm and sets the power emitted by the radio. * If the antenna has a gain, it must be substracted from the specified value to * achieve the correct transmission power. * * @param tx_pow power, in dBm */ void ttn_set_max_tx_pow(int tx_pow); /** * @brief Gets current RX/TX window * @return window */ ttn_rx_tx_window_t ttn_rx_tx_window(void); /** * @brief Gets the RF settings for the specified window * @param window RX/TX window (valid values are @ref TTN_WINDOW_TX, @ref TTN_WINDOW_RX1 and @ref TTN_WINDOW_RX2 */ ttn_rf_settings_t ttn_get_rf_settings(ttn_rx_tx_window_t window); /** * @brief Gets the RF settings of the last (or ongoing) transmission. * @return RF settings */ ttn_rf_settings_t ttn_tx_settings(void); /** * @brief Gets the RF settings of the last (or ongoing) reception of RX window 1. * @return RF settings */ ttn_rf_settings_t ttn_rx1_settings(void); /** * @brief Gets the RF settings of the last (or ongoing) reception of RX window 2. * @return RF settings */ ttn_rf_settings_t ttn_rx2_settings(void); /** * @brief Gets the received signal strength indicator (RSSI). * * RSSI is the measured signal strength of the last recevied message (incl. join responses). * * @return RSSI, in dBm */ int ttn_rssi(); /** * @} */ #ifdef __cplusplus } #endif #endif