C/C++ - Industrial Dual Relay Bricklet

This is the description of the C/C++ API bindings for the Industrial Dual Relay Bricklet. General information and technical specifications for the Industrial Dual Relay Bricklet are summarized in its hardware description.

An installation guide for the C/C++ API bindings is part of their general description.

Examples

The example code below is Public Domain (CC0 1.0).

Simple

Download (example_simple.c)

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#define IPCON_EXPOSE_MILLISLEEP

#include <stdio.h>

#include "ip_connection.h"
#include "bricklet_industrial_dual_relay.h"

#define HOST "localhost"
#define PORT 4223
#define UID "XYZ" // Change XYZ to the UID of your Industrial Dual Relay Bricklet

int main(void) {
    // Create IP connection
    IPConnection ipcon;
    ipcon_create(&ipcon);

    // Create device object
    IndustrialDualRelay idr;
    industrial_dual_relay_create(&idr, UID, &ipcon);

    // Connect to brickd
    if(ipcon_connect(&ipcon, HOST, PORT) < 0) {
        fprintf(stderr, "Could not connect\n");
        return 1;
    }
    // Don't use device before ipcon is connected

    // Turn relays alternating on/off 10 times with 1 second delay
    int i;
    for(i = 0; i < 5; ++i) {
        millisleep(1000);
        industrial_dual_relay_set_value(&idr, true, false);
        millisleep(1000);
        industrial_dual_relay_set_value(&idr, false, true);
    }

    printf("Press key to exit\n");
    getchar();
    industrial_dual_relay_destroy(&idr);
    ipcon_destroy(&ipcon); // Calls ipcon_disconnect internally
    return 0;
}

API

Every function of the C/C++ bindings returns an integer which describes an error code. Data returned from the device, when a getter is called, is handled via output parameters. These parameters are labeled with the ret_ prefix.

Possible error codes are:

  • E_OK = 0
  • E_TIMEOUT = -1
  • E_NO_STREAM_SOCKET = -2
  • E_HOSTNAME_INVALID = -3
  • E_NO_CONNECT = -4
  • E_NO_THREAD = -5
  • E_NOT_ADDED = -6 (unused since C/C++ bindings version 2.0.0)
  • E_ALREADY_CONNECTED = -7
  • E_NOT_CONNECTED = -8
  • E_INVALID_PARAMETER = -9
  • E_NOT_SUPPORTED = -10
  • E_UNKNOWN_ERROR_CODE = -11
  • E_STREAM_OUT_OF_SYNC = -12
  • E_INVALID_UID = -13
  • E_NON_ASCII_CHAR_IN_SECRET = -14

as defined in ip_connection.h.

All functions listed below are thread-safe.

Basic Functions

void industrial_dual_relay_create(IndustrialDualRelay *industrial_dual_relay, const char *uid, IPConnection *ipcon)
Parameters:
  • industrial_dual_relay – Type: IndustrialDualRelay *
  • uid – Type: const char *
  • ipcon – Type: IPConnection *

Creates the device object industrial_dual_relay with the unique device ID uid and adds it to the IPConnection ipcon:

IndustrialDualRelay industrial_dual_relay;
industrial_dual_relay_create(&industrial_dual_relay, "YOUR_DEVICE_UID", &ipcon);

This device object can be used after the IP connection has been connected (see examples above).

void industrial_dual_relay_destroy(IndustrialDualRelay *industrial_dual_relay)
Parameters:
  • industrial_dual_relay – Type: IndustrialDualRelay *

Removes the device object industrial_dual_relay from its IPConnection and destroys it. The device object cannot be used anymore afterwards.

int industrial_dual_relay_set_value(IndustrialDualRelay *industrial_dual_relay, bool channel0, bool channel1)
Parameters:
  • industrial_dual_relay – Type: IndustrialDualRelay *
  • channel0 – Type: bool, Default: false
  • channel1 – Type: bool, Default: false
Returns:
  • error_code – Type: int

Sets the state of the relays, true means on and false means off. For example: (true, false) turns relay 0 on and relay 1 off.

If you just want to set one of the relays and don't know the current state of the other relay, you can get the state with industrial_dual_relay_get_value() or you can use industrial_dual_relay_set_selected_value().

All running monoflop timers will be aborted if this function is called.

int industrial_dual_relay_get_value(IndustrialDualRelay *industrial_dual_relay, bool *ret_channel0, bool *ret_channel1)
Parameters:
  • industrial_dual_relay – Type: IndustrialDualRelay *
Output Parameters:
  • ret_channel0 – Type: bool, Default: false
  • ret_channel1 – Type: bool, Default: false
Returns:
  • error_code – Type: int

Returns the state of the relays, true means on and false means off.

Advanced Functions

int industrial_dual_relay_set_monoflop(IndustrialDualRelay *industrial_dual_relay, uint8_t channel, bool value, uint32_t time)
Parameters:
  • industrial_dual_relay – Type: IndustrialDualRelay *
  • channel – Type: uint8_t, Range: [0 to 1]
  • value – Type: bool
  • time – Type: uint32_t, Unit: 1 ms, Range: [0 to 232 - 1]
Returns:
  • error_code – Type: int

The first parameter can be 0 or 1 (relay 0 or relay 1). The second parameter is the desired state of the relay (true means on and false means off). The third parameter indicates the time that the relay should hold the state.

If this function is called with the parameters (1, true, 1500): Relay 1 will turn on and in 1.5s it will turn off again.

A monoflop can be used as a failsafe mechanism. For example: Lets assume you have a RS485 bus and a Industrial Dual Relay Bricklet connected to one of the slave stacks. You can now call this function every second, with a time parameter of two seconds. The relay will be on all the time. If now the RS485 connection is lost, the relay will turn off in at most two seconds.

int industrial_dual_relay_get_monoflop(IndustrialDualRelay *industrial_dual_relay, uint8_t channel, bool *ret_value, uint32_t *ret_time, uint32_t *ret_time_remaining)
Parameters:
  • industrial_dual_relay – Type: IndustrialDualRelay *
  • channel – Type: uint8_t, Range: [0 to 1]
Output Parameters:
  • ret_value – Type: bool
  • ret_time – Type: uint32_t, Unit: 1 ms, Range: [0 to 232 - 1]
  • ret_time_remaining – Type: uint32_t, Unit: 1 ms, Range: [0 to 232 - 1]
Returns:
  • error_code – Type: int

Returns (for the given relay) the current state and the time as set by industrial_dual_relay_set_monoflop() as well as the remaining time until the state flips.

If the timer is not running currently, the remaining time will be returned as 0.

int industrial_dual_relay_set_selected_value(IndustrialDualRelay *industrial_dual_relay, uint8_t channel, bool value)
Parameters:
  • industrial_dual_relay – Type: IndustrialDualRelay *
  • channel – Type: uint8_t, Range: [0 to 1]
  • value – Type: bool
Returns:
  • error_code – Type: int

Sets the state of the selected relay, true means on and false means off.

A running monoflop timer for the selected relay will be aborted if this function is called.

The other relay remains untouched.

int industrial_dual_relay_get_spitfp_error_count(IndustrialDualRelay *industrial_dual_relay, uint32_t *ret_error_count_ack_checksum, uint32_t *ret_error_count_message_checksum, uint32_t *ret_error_count_frame, uint32_t *ret_error_count_overflow)
Parameters:
  • industrial_dual_relay – Type: IndustrialDualRelay *
Output Parameters:
  • ret_error_count_ack_checksum – Type: uint32_t, Range: [0 to 232 - 1]
  • ret_error_count_message_checksum – Type: uint32_t, Range: [0 to 232 - 1]
  • ret_error_count_frame – Type: uint32_t, Range: [0 to 232 - 1]
  • ret_error_count_overflow – Type: uint32_t, Range: [0 to 232 - 1]
Returns:
  • error_code – Type: int

Returns the error count for the communication between Brick and Bricklet.

The errors are divided into

  • ACK checksum errors,
  • message checksum errors,
  • framing errors and
  • overflow errors.

The errors counts are for errors that occur on the Bricklet side. All Bricks have a similar function that returns the errors on the Brick side.

int industrial_dual_relay_set_bootloader_mode(IndustrialDualRelay *industrial_dual_relay, uint8_t mode, uint8_t *ret_status)
Parameters:
  • industrial_dual_relay – Type: IndustrialDualRelay *
  • mode – Type: uint8_t, Range: See constants
Output Parameters:
  • ret_status – Type: uint8_t, Range: See constants
Returns:
  • error_code – Type: int

Sets the bootloader mode and returns the status after the requested mode change was instigated.

You can change from bootloader mode to firmware mode and vice versa. A change from bootloader mode to firmware mode will only take place if the entry function, device identifier and CRC are present and correct.

This function is used by Brick Viewer during flashing. It should not be necessary to call it in a normal user program.

The following constants are available for this function:

For mode:

  • INDUSTRIAL_DUAL_RELAY_BOOTLOADER_MODE_BOOTLOADER = 0
  • INDUSTRIAL_DUAL_RELAY_BOOTLOADER_MODE_FIRMWARE = 1
  • INDUSTRIAL_DUAL_RELAY_BOOTLOADER_MODE_BOOTLOADER_WAIT_FOR_REBOOT = 2
  • INDUSTRIAL_DUAL_RELAY_BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_REBOOT = 3
  • INDUSTRIAL_DUAL_RELAY_BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_ERASE_AND_REBOOT = 4

For ret_status:

  • INDUSTRIAL_DUAL_RELAY_BOOTLOADER_STATUS_OK = 0
  • INDUSTRIAL_DUAL_RELAY_BOOTLOADER_STATUS_INVALID_MODE = 1
  • INDUSTRIAL_DUAL_RELAY_BOOTLOADER_STATUS_NO_CHANGE = 2
  • INDUSTRIAL_DUAL_RELAY_BOOTLOADER_STATUS_ENTRY_FUNCTION_NOT_PRESENT = 3
  • INDUSTRIAL_DUAL_RELAY_BOOTLOADER_STATUS_DEVICE_IDENTIFIER_INCORRECT = 4
  • INDUSTRIAL_DUAL_RELAY_BOOTLOADER_STATUS_CRC_MISMATCH = 5
int industrial_dual_relay_get_bootloader_mode(IndustrialDualRelay *industrial_dual_relay, uint8_t *ret_mode)
Parameters:
  • industrial_dual_relay – Type: IndustrialDualRelay *
Output Parameters:
  • ret_mode – Type: uint8_t, Range: See constants
Returns:
  • error_code – Type: int

Returns the current bootloader mode, see industrial_dual_relay_set_bootloader_mode().

The following constants are available for this function:

For ret_mode:

  • INDUSTRIAL_DUAL_RELAY_BOOTLOADER_MODE_BOOTLOADER = 0
  • INDUSTRIAL_DUAL_RELAY_BOOTLOADER_MODE_FIRMWARE = 1
  • INDUSTRIAL_DUAL_RELAY_BOOTLOADER_MODE_BOOTLOADER_WAIT_FOR_REBOOT = 2
  • INDUSTRIAL_DUAL_RELAY_BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_REBOOT = 3
  • INDUSTRIAL_DUAL_RELAY_BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_ERASE_AND_REBOOT = 4
int industrial_dual_relay_set_write_firmware_pointer(IndustrialDualRelay *industrial_dual_relay, uint32_t pointer)
Parameters:
  • industrial_dual_relay – Type: IndustrialDualRelay *
  • pointer – Type: uint32_t, Unit: 1 B, Range: [0 to 232 - 1]
Returns:
  • error_code – Type: int

Sets the firmware pointer for industrial_dual_relay_write_firmware(). The pointer has to be increased by chunks of size 64. The data is written to flash every 4 chunks (which equals to one page of size 256).

This function is used by Brick Viewer during flashing. It should not be necessary to call it in a normal user program.

int industrial_dual_relay_write_firmware(IndustrialDualRelay *industrial_dual_relay, uint8_t data[64], uint8_t *ret_status)
Parameters:
  • industrial_dual_relay – Type: IndustrialDualRelay *
  • data – Type: uint8_t[64], Range: [0 to 255]
Output Parameters:
  • ret_status – Type: uint8_t, Range: [0 to 255]
Returns:
  • error_code – Type: int

Writes 64 Bytes of firmware at the position as written by industrial_dual_relay_set_write_firmware_pointer() before. The firmware is written to flash every 4 chunks.

You can only write firmware in bootloader mode.

This function is used by Brick Viewer during flashing. It should not be necessary to call it in a normal user program.

int industrial_dual_relay_set_status_led_config(IndustrialDualRelay *industrial_dual_relay, uint8_t config)
Parameters:
  • industrial_dual_relay – Type: IndustrialDualRelay *
  • config – Type: uint8_t, Range: See constants, Default: 3
Returns:
  • error_code – Type: int

Sets the status LED configuration. By default the LED shows communication traffic between Brick and Bricklet, it flickers once for every 10 received data packets.

You can also turn the LED permanently on/off or show a heartbeat.

If the Bricklet is in bootloader mode, the LED is will show heartbeat by default.

The following constants are available for this function:

For config:

  • INDUSTRIAL_DUAL_RELAY_STATUS_LED_CONFIG_OFF = 0
  • INDUSTRIAL_DUAL_RELAY_STATUS_LED_CONFIG_ON = 1
  • INDUSTRIAL_DUAL_RELAY_STATUS_LED_CONFIG_SHOW_HEARTBEAT = 2
  • INDUSTRIAL_DUAL_RELAY_STATUS_LED_CONFIG_SHOW_STATUS = 3
int industrial_dual_relay_get_status_led_config(IndustrialDualRelay *industrial_dual_relay, uint8_t *ret_config)
Parameters:
  • industrial_dual_relay – Type: IndustrialDualRelay *
Output Parameters:
  • ret_config – Type: uint8_t, Range: See constants, Default: 3
Returns:
  • error_code – Type: int

Returns the configuration as set by industrial_dual_relay_set_status_led_config()

The following constants are available for this function:

For ret_config:

  • INDUSTRIAL_DUAL_RELAY_STATUS_LED_CONFIG_OFF = 0
  • INDUSTRIAL_DUAL_RELAY_STATUS_LED_CONFIG_ON = 1
  • INDUSTRIAL_DUAL_RELAY_STATUS_LED_CONFIG_SHOW_HEARTBEAT = 2
  • INDUSTRIAL_DUAL_RELAY_STATUS_LED_CONFIG_SHOW_STATUS = 3
int industrial_dual_relay_get_chip_temperature(IndustrialDualRelay *industrial_dual_relay, int16_t *ret_temperature)
Parameters:
  • industrial_dual_relay – Type: IndustrialDualRelay *
Output Parameters:
  • ret_temperature – Type: int16_t, Unit: 1 °C, Range: [-215 to 215 - 1]
Returns:
  • error_code – Type: int

Returns the temperature as measured inside the microcontroller. The value returned is not the ambient temperature!

The temperature is only proportional to the real temperature and it has bad accuracy. Practically it is only useful as an indicator for temperature changes.

int industrial_dual_relay_reset(IndustrialDualRelay *industrial_dual_relay)
Parameters:
  • industrial_dual_relay – Type: IndustrialDualRelay *
Returns:
  • error_code – Type: int

Calling this function will reset the Bricklet. All configurations will be lost.

After a reset you have to create new device objects, calling functions on the existing ones will result in undefined behavior!

int industrial_dual_relay_write_uid(IndustrialDualRelay *industrial_dual_relay, uint32_t uid)
Parameters:
  • industrial_dual_relay – Type: IndustrialDualRelay *
  • uid – Type: uint32_t, Range: [0 to 232 - 1]
Returns:
  • error_code – Type: int

Writes a new UID into flash. If you want to set a new UID you have to decode the Base58 encoded UID string into an integer first.

We recommend that you use Brick Viewer to change the UID.

int industrial_dual_relay_read_uid(IndustrialDualRelay *industrial_dual_relay, uint32_t *ret_uid)
Parameters:
  • industrial_dual_relay – Type: IndustrialDualRelay *
Output Parameters:
  • ret_uid – Type: uint32_t, Range: [0 to 232 - 1]
Returns:
  • error_code – Type: int

Returns the current UID as an integer. Encode as Base58 to get the usual string version.

int industrial_dual_relay_get_identity(IndustrialDualRelay *industrial_dual_relay, char ret_uid[8], char ret_connected_uid[8], char *ret_position, uint8_t ret_hardware_version[3], uint8_t ret_firmware_version[3], uint16_t *ret_device_identifier)
Parameters:
  • industrial_dual_relay – Type: IndustrialDualRelay *
Output Parameters:
  • ret_uid – Type: char[8]
  • ret_connected_uid – Type: char[8]
  • ret_position – Type: char, Range: ['a' to 'h', 'i', 'z']
  • ret_hardware_version – Type: uint8_t[3]
    • 0: major – Type: uint8_t, Range: [0 to 255]
    • 1: minor – Type: uint8_t, Range: [0 to 255]
    • 2: revision – Type: uint8_t, Range: [0 to 255]
  • ret_firmware_version – Type: uint8_t[3]
    • 0: major – Type: uint8_t, Range: [0 to 255]
    • 1: minor – Type: uint8_t, Range: [0 to 255]
    • 2: revision – Type: uint8_t, Range: [0 to 255]
  • ret_device_identifier – Type: uint16_t, Range: [0 to 216 - 1]
Returns:
  • error_code – Type: int

Returns the UID, the UID where the Bricklet is connected to, the position, the hardware and firmware version as well as the device identifier.

The position can be 'a', 'b', 'c', 'd', 'e', 'f', 'g' or 'h' (Bricklet Port). The Raspberry Pi HAT (Zero) Brick is always at position 'i' and the Bricklet connected to an Isolator Bricklet is always as position 'z'.

The device identifier numbers can be found here. There is also a constant for the device identifier of this Bricklet.

Callback Configuration Functions

void industrial_dual_relay_register_callback(IndustrialDualRelay *industrial_dual_relay, int16_t callback_id, void (*function)(void), void *user_data)
Parameters:
  • industrial_dual_relay – Type: IndustrialDualRelay *
  • callback_id – Type: int16_t
  • function – Type: void (*)(void)
  • user_data – Type: void *

Registers the given function with the given callback_id. The user_data will be passed as the last parameter to the function.

The available callback IDs with corresponding function signatures are listed below.

Callbacks

Callbacks can be registered to receive time critical or recurring data from the device. The registration is done with the industrial_dual_relay_register_callback() function:

void my_callback(int value, void *user_data) {
    printf("Value: %d\n", value);
}

industrial_dual_relay_register_callback(&industrial_dual_relay,
                                        INDUSTRIAL_DUAL_RELAY_CALLBACK_EXAMPLE,
                                        (void (*)(void))my_callback,
                                        NULL);

The available constants with corresponding function signatures are described below.

Note

Using callbacks for recurring events is always preferred compared to using getters. It will use less USB bandwidth and the latency will be a lot better, since there is no round trip time.

INDUSTRIAL_DUAL_RELAY_CALLBACK_MONOFLOP_DONE
void callback(uint8_t channel, bool value, void *user_data)
Callback Parameters:
  • channel – Type: uint8_t, Range: [0 to 1]
  • value – Type: bool
  • user_data – Type: void *

This callback is triggered whenever a monoflop timer reaches 0. The parameters contain the relay and the current state of the relay (the state after the monoflop).

Virtual Functions

Virtual functions don't communicate with the device itself, but operate only on the API bindings device object. They can be called without the corresponding IP Connection object being connected.

int industrial_dual_relay_get_api_version(IndustrialDualRelay *industrial_dual_relay, uint8_t ret_api_version[3])
Parameters:
  • industrial_dual_relay – Type: IndustrialDualRelay *
Output Parameters:
  • ret_api_version – Type: uint8_t[3]
    • 0: major – Type: uint8_t, Range: [0 to 255]
    • 1: minor – Type: uint8_t, Range: [0 to 255]
    • 2: revision – Type: uint8_t, Range: [0 to 255]
Returns:
  • error_code – Type: int

Returns the version of the API definition implemented by this API bindings. This is neither the release version of this API bindings nor does it tell you anything about the represented Brick or Bricklet.

int industrial_dual_relay_get_response_expected(IndustrialDualRelay *industrial_dual_relay, uint8_t function_id, bool *ret_response_expected)
Parameters:
  • industrial_dual_relay – Type: IndustrialDualRelay *
  • function_id – Type: uint8_t, Range: See constants
Output Parameters:
  • ret_response_expected – Type: bool
Returns:
  • error_code – Type: int

Returns the response expected flag for the function specified by the function ID parameter. It is true if the function is expected to send a response, false otherwise.

For getter functions this is enabled by default and cannot be disabled, because those functions will always send a response. For callback configuration functions it is enabled by default too, but can be disabled by industrial_dual_relay_set_response_expected(). For setter functions it is disabled by default and can be enabled.

Enabling the response expected flag for a setter function allows to detect timeouts and other error conditions calls of this setter as well. The device will then send a response for this purpose. If this flag is disabled for a setter function then no response is send and errors are silently ignored, because they cannot be detected.

The following constants are available for this function:

For function_id:

  • INDUSTRIAL_DUAL_RELAY_FUNCTION_SET_VALUE = 1
  • INDUSTRIAL_DUAL_RELAY_FUNCTION_SET_MONOFLOP = 3
  • INDUSTRIAL_DUAL_RELAY_FUNCTION_SET_SELECTED_VALUE = 6
  • INDUSTRIAL_DUAL_RELAY_FUNCTION_SET_WRITE_FIRMWARE_POINTER = 237
  • INDUSTRIAL_DUAL_RELAY_FUNCTION_SET_STATUS_LED_CONFIG = 239
  • INDUSTRIAL_DUAL_RELAY_FUNCTION_RESET = 243
  • INDUSTRIAL_DUAL_RELAY_FUNCTION_WRITE_UID = 248
int industrial_dual_relay_set_response_expected(IndustrialDualRelay *industrial_dual_relay, uint8_t function_id, bool response_expected)
Parameters:
  • industrial_dual_relay – Type: IndustrialDualRelay *
  • function_id – Type: uint8_t, Range: See constants
  • response_expected – Type: bool
Returns:
  • error_code – Type: int

Changes the response expected flag of the function specified by the function ID parameter. This flag can only be changed for setter (default value: false) and callback configuration functions (default value: true). For getter functions it is always enabled.

Enabling the response expected flag for a setter function allows to detect timeouts and other error conditions calls of this setter as well. The device will then send a response for this purpose. If this flag is disabled for a setter function then no response is send and errors are silently ignored, because they cannot be detected.

The following constants are available for this function:

For function_id:

  • INDUSTRIAL_DUAL_RELAY_FUNCTION_SET_VALUE = 1
  • INDUSTRIAL_DUAL_RELAY_FUNCTION_SET_MONOFLOP = 3
  • INDUSTRIAL_DUAL_RELAY_FUNCTION_SET_SELECTED_VALUE = 6
  • INDUSTRIAL_DUAL_RELAY_FUNCTION_SET_WRITE_FIRMWARE_POINTER = 237
  • INDUSTRIAL_DUAL_RELAY_FUNCTION_SET_STATUS_LED_CONFIG = 239
  • INDUSTRIAL_DUAL_RELAY_FUNCTION_RESET = 243
  • INDUSTRIAL_DUAL_RELAY_FUNCTION_WRITE_UID = 248
int industrial_dual_relay_set_response_expected_all(IndustrialDualRelay *industrial_dual_relay, bool response_expected)
Parameters:
  • industrial_dual_relay – Type: IndustrialDualRelay *
  • response_expected – Type: bool
Returns:
  • error_code – Type: int

Changes the response expected flag for all setter and callback configuration functions of this device at once.

Constants

INDUSTRIAL_DUAL_RELAY_DEVICE_IDENTIFIER

This constant is used to identify a Industrial Dual Relay Bricklet.

The industrial_dual_relay_get_identity() function and the IPCON_CALLBACK_ENUMERATE callback of the IP Connection have a device_identifier parameter to specify the Brick's or Bricklet's type.

INDUSTRIAL_DUAL_RELAY_DEVICE_DISPLAY_NAME

This constant represents the human readable name of a Industrial Dual Relay Bricklet.