C/C++ - Industrial Digital Out 4 Bricklet

This is the description of the C/C++ API bindings for the Industrial Digital Out 4 Bricklet. General information and technical specifications for the Industrial Digital Out 4 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_digital_out_4.h"

#define HOST "localhost"
#define PORT 4223
#define UID "XYZ" // Change XYZ to the UID of your Industrial Digital Out 4 Bricklet

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

    // Create device object
    IndustrialDigitalOut4 ido4;
    industrial_digital_out_4_create(&ido4, 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

    // Set pins alternating high/low 10 times with 100ms delay
    int i;
    for(i = 0; i < 10; ++i) {
        millisleep(100);
        industrial_digital_out_4_set_value(&ido4, 1 << 0);
        millisleep(100);
        industrial_digital_out_4_set_value(&ido4, 1 << 1);
        millisleep(100);
        industrial_digital_out_4_set_value(&ido4, 1 << 2);
        millisleep(100);
        industrial_digital_out_4_set_value(&ido4, 1 << 3);
    }

    printf("Press key to exit\n");
    getchar();
    industrial_digital_out_4_destroy(&ido4);
    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 call by reference. 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 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

as defined in ip_connection.h.

All functions listed below are thread-safe.

Basic Functions

void industrial_digital_out_4_create(IndustrialDigitalOut4 *industrial_digital_out_4, const char *uid, IPConnection *ipcon)

Creates the device object industrial_digital_out_4 with the unique device ID uid and adds it to the IPConnection ipcon:

IndustrialDigitalOut4 industrial_digital_out_4;
industrial_digital_out_4_create(&industrial_digital_out_4, "YOUR_DEVICE_UID", &ipcon);

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

void industrial_digital_out_4_destroy(IndustrialDigitalOut4 *industrial_digital_out_4)

Removes the device object industrial_digital_out_4 from its IPConnection and destroys it. The device object cannot be used anymore afterwards.

int industrial_digital_out_4_set_value(IndustrialDigitalOut4 *industrial_digital_out_4, uint16_t value_mask)

Sets the output value with a bitmask (16bit). A 1 in the bitmask means high and a 0 in the bitmask means low.

For example: The value 3 or 0b0011 will turn pins 0-1 high and the other pins low.

If no groups are used (see industrial_digital_out_4_set_group()), the pins correspond to the markings on the Digital Out 4 Bricklet.

If groups are used, the pins correspond to the element in the group. Element 1 in the group will get pins 0-3, element 2 pins 4-7, element 3 pins 8-11 and element 4 pins 12-15.

int industrial_digital_out_4_get_value(IndustrialDigitalOut4 *industrial_digital_out_4, uint16_t *ret_value_mask)

Returns the bitmask as set by industrial_digital_out_4_set_value().

int industrial_digital_out_4_set_selected_values(IndustrialDigitalOut4 *industrial_digital_out_4, uint16_t selection_mask, uint16_t value_mask)

Sets the output value with a bitmask, according to the selection mask. The bitmask is 16 bit long, true refers to high and false refers to low.

For example: The values (3, 1) or (0b0011, 0b0001) will turn pin 0 high, pin 1 low the other pins remain untouched.

If no groups are used (see industrial_digital_out_4_set_group()), the pins correspond to the markings on the Digital Out 4 Bricklet.

If groups are used, the pins correspond to the element in the group. Element 1 in the group will get pins 0-3, element 2 pins 4-7, element 3 pins 8-11 and element 4 pins 12-15.

Advanced Functions

int industrial_digital_out_4_set_monoflop(IndustrialDigitalOut4 *industrial_digital_out_4, uint16_t selection_mask, uint16_t value_mask, uint32_t time)

Configures a monoflop of the pins specified by the first parameter bitmask.

The second parameter is a bitmask with the desired value of the specified pins. A 1 in the bitmask means high and a 0 in the bitmask means low.

The third parameter indicates the time (in ms) that the pins should hold the value.

If this function is called with the parameters (9, 1, 1500) or (0b1001, 0b0001, 1500): Pin 0 will get high and pin 3 will get low. In 1.5s pin 0 will get low and pin 3 will get high again.

A monoflop can be used as a fail-safe mechanism. For example: Lets assume you have a RS485 bus and a Digital Out 4 Bricklet connected to one of the slave stacks. You can now call this function every second, with a time parameter of two seconds and pin 0 high. Pin 0 will be high all the time. If now the RS485 connection is lost, then pin 0 will turn low in at most two seconds.

int industrial_digital_out_4_get_monoflop(IndustrialDigitalOut4 *industrial_digital_out_4, uint8_t pin, uint16_t *ret_value, uint32_t *ret_time, uint32_t *ret_time_remaining)

Returns (for the given pin) the current value and the time as set by industrial_digital_out_4_set_monoflop() as well as the remaining time until the value flips.

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

int industrial_digital_out_4_set_group(IndustrialDigitalOut4 *industrial_digital_out_4, char group[4])

Sets a group of Digital Out 4 Bricklets that should work together. You can find Bricklets that can be grouped together with industrial_digital_out_4_get_available_for_group().

The group consists of 4 elements. Element 1 in the group will get pins 0-3, element 2 pins 4-7, element 3 pins 8-11 and element 4 pins 12-15.

Each element can either be one of the ports ('a' to 'd') or 'n' if it should not be used.

For example: If you have two Digital Out 4 Bricklets connected to port A and port B respectively, you could call with ['a', 'b', 'n', 'n'].

Now the pins on the Digital Out 4 on port A are assigned to 0-3 and the pins on the Digital Out 4 on port B are assigned to 4-7. It is now possible to call industrial_digital_out_4_set_value() and control two Bricklets at the same time.

int industrial_digital_out_4_get_group(IndustrialDigitalOut4 *industrial_digital_out_4, char ret_group[4])

Returns the group as set by industrial_digital_out_4_set_group()

int industrial_digital_out_4_get_available_for_group(IndustrialDigitalOut4 *industrial_digital_out_4, uint8_t *ret_available)

Returns a bitmask of ports that are available for grouping. For example the value 5 or 0b0101 means: Port A and port C are connected to Bricklets that can be grouped together.

int industrial_digital_out_4_get_api_version(IndustrialDigitalOut4 *industrial_digital_out_4, uint8_t ret_api_version[3])

Returns the version of the API definition (major, minor, revision) 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_digital_out_4_get_response_expected(IndustrialDigitalOut4 *industrial_digital_out_4, uint8_t function_id, bool *ret_response_expected)

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_digital_out_4_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.

See industrial_digital_out_4_set_response_expected() for the list of function ID defines available for this function.

int industrial_digital_out_4_set_response_expected(IndustrialDigitalOut4 *industrial_digital_out_4, uint8_t function_id, bool response_expected)

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 function ID defines are available for this function:

  • INDUSTRIAL_DIGITAL_OUT_4_FUNCTION_SET_VALUE = 1
  • INDUSTRIAL_DIGITAL_OUT_4_FUNCTION_SET_MONOFLOP = 3
  • INDUSTRIAL_DIGITAL_OUT_4_FUNCTION_SET_GROUP = 5
  • INDUSTRIAL_DIGITAL_OUT_4_FUNCTION_SET_SELECTED_VALUES = 9
int industrial_digital_out_4_set_response_expected_all(IndustrialDigitalOut4 *industrial_digital_out_4, bool response_expected)

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

int industrial_digital_out_4_get_identity(IndustrialDigitalOut4 *industrial_digital_out_4, 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)

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' or 'd'.

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_digital_out_4_register_callback(IndustrialDigitalOut4 *industrial_digital_out_4, int16_t callback_id, void *function, void *user_data)

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_digital_out_4_register_callback() function. The parameters consist of the device object, the callback ID, the callback function and optional user data:

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

industrial_digital_out_4_register_callback(&industrial_digital_out_4, INDUSTRIAL_DIGITAL_OUT_4_CALLBACK_EXAMPLE, (void *)my_callback, NULL);

The available constants with corresponding callback 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_DIGITAL_OUT_4_CALLBACK_MONOFLOP_DONE
void callback(uint16_t selection_mask, uint16_t value_mask, void *user_data)

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

Constants

INDUSTRIAL_DIGITAL_OUT_4_DEVICE_IDENTIFIER

This constant is used to identify a Industrial Digital Out 4 Bricklet.

The industrial_digital_out_4_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_DIGITAL_OUT_4_DEVICE_DISPLAY_NAME

This constant represents the human readable name of a Industrial Digital Out 4 Bricklet.