ESP32-SX/CX Iridium Modem

Overview

The purpose of this library is to provide a drop-in solution for interactions on the Iridium Satellite network using AT commands. The library uses the ESP32 UART bus with different queues/pthread to manage messages in an asynchronous or synchronous way.

Dependencies

• ESP IDF
• FreeRTOS

---

Hardware

NOTE: The default serial baud rate is 19200 with most of the RockBlock pinouts operating on 3.3v logic.

1. RXD -> Serial output from device
2. CTS -> Clear to Send
3. RTS -> Ready To Send
4. NET -> Network Available
5. RI -> Ring Indicator
6. TXD -> Serial input to device
7. SLP -> Sleep control
8. 5V -> 5V in power supply
9. BAT -> 3.7V power supply
10. GND -> Ground

---

Documentation

Construct an iridium satellite communication struct with callbacks.

iridium_t *satcom = iridium_default_configuration();
satcom->callback = &cb_satcom;
satcom->message_callback = &cb_message;

Configure UART bus ports.

/* UART Port Configuration */
satcom->uart_number = UART_NUM_1;
satcom->uart_txn_number = GPIO_NUM_17;
satcom->uart_rxd_number = GPIO_NUM_18;
satcom->uart_rts_number = UART_PIN_NO_CHANGE;
satcom->uart_cts_number = UART_PIN_NO_CHANGE;

Setup satellite modem.

iridium_config(satcom) // return SAT_OK or SAT_ERROR

Once a SAT_OK status is received from the satellite configuration, the following methods are available.

---

Enabled or disable the ring notification on the modem.

/**
 * @param satcom the iridium_t struct pointer.
 * @param enabled the ring notification.
 * @return a iridium_result_t with metadata.
 */
iridium_result_t iridium_config_ring(iridium_t *satcom, bool enabled);

---

Transmit a message to the iridium network.

/**
 * @param satcom the iridium_t struct pointer.
 * @param message to be sent.
 * @return a iridium_result_t with metadata.
 */
iridium_result_t iridium_tx_message(iridium_t *satcom, char *message);

---

Send AT command with data.

/**
 * @param satcom the iridium_t struct pointer.
 * @param command the iridium modem AT command.
 * @param rdata the raw data. 
 * @param wait_response wait for a responce from the modem.
 * @param wait_interval the amount of time in ms for wait interval check.
 * @return a iridium_result_t with metadata.
 */
iridium_result_t iridium_send(iridium_t* satcom, iridium_command_t command, char *rdata, bool wait_response, int wait_interval);

Example

#include "iridium.h"

static const char *TAG_CORE = "iridium_example";

/* Callbacks */
void cb_satcom(iridium_t* satcom, iridium_command_t command, iridium_status_t status) { 
    if (status == SAT_OK) {
        switch (command) {
            case AT_CSQ:
                ESP_LOGI(TAG_CORE, "Signal Strength [0-5]: %d", satcom->signal_strength);
                break;
            case AT_CGMM:
                ESP_LOGI(TAG_CORE, "Model Identification: %s", satcom->model_identification);
                break;
            case AT_CGMI:
                ESP_LOGI(TAG_CORE, "Manufacturer Identification: %s", satcom->manufacturer_identification);
                break;
            default:
                break;
        }
    }
}

void cb_message(iridium_t* satcom, char* data) { 
    ESP_LOGI(TAG_CORE, "MESSAGE[INCOMING] %s", data);
}

/* Configuration Iridium SatCom */
iridium_t *satcom = iridium_default_configuration();
satcom->callback = &cb_satcom;
satcom->message_callback = &cb_message;
/* UART Port Configuration */
satcom->uart_number = UART_NUM_1;
satcom->uart_txn_number = GPIO_NUM_17;
satcom->uart_rxd_number = GPIO_NUM_18;
satcom->uart_rts_number = UART_PIN_NO_CHANGE;
satcom->uart_cts_number = UART_PIN_NO_CHANGE;
    
/* Initialized */
if (iridium_config(satcom) == SAT_OK) {
    ESP_LOGI(TAG_CORE, "Iridium Modem [Initialized]");
}

/* Allow Ring Triggers */
iridium_result_t ring = iridium_config_ring(satcom, true);
if (ring.status == SAT_OK) {
    ESP_LOGI(TAG_CORE, "Iridium Modem [Ring Enabled]");
}

Contributing

When contributing to this repository, please first discuss the change you wish to make via issue, email, or any other method with the owners of this repository before making a change.

Please note we have a code of conduct, please follow it in all your interactions with the project.

Pull Request Process

1. Ensure any install or build dependencies are removed before the end of the layer when doing a build.
2. Update the README.md with details of changes to the interface, this includes new environment variables, exposed ports, useful file locations and container parameters.
3. You may merge the Pull Request in once you have the sign-off of two other developers, or if you do not have permission to do that, you may request the second reviewer to merge it for you.

Code of Conduct

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