C/C++ - Analog Out Bricklet

This is the description of the C/C++ API bindings for the Analog Out Bricklet. General information and technical specifications for the Analog Out 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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#include <stdio.h>

#include "ip_connection.h"
#include "bricklet_analog_out.h"

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

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

    // Create device object
    AnalogOut ao;
    analog_out_create(&ao, 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 output voltage to 3.3V
    analog_out_set_voltage(&ao, 3300);

    printf("Press key to exit\n");
    getchar();
    analog_out_destroy(&ao);
    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 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

as defined in ip_connection.h.

All functions listed below are thread-safe.

Basic Functions

void analog_out_create(AnalogOut *analog_out, const char *uid, IPConnection *ipcon)

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

AnalogOut analog_out;
analog_out_create(&analog_out, "YOUR_DEVICE_UID", &ipcon);

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

void analog_out_destroy(AnalogOut *analog_out)

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

int analog_out_set_voltage(AnalogOut *analog_out, uint16_t voltage)

Sets the voltage in mV. The possible range is 0V to 5V (0-5000). Calling this function will set the mode to 0 (see analog_out_set_mode()).

The default value is 0 (with mode 1).

int analog_out_get_voltage(AnalogOut *analog_out, uint16_t *ret_voltage)

Returns the voltage as set by analog_out_set_voltage().

int analog_out_set_mode(AnalogOut *analog_out, uint8_t mode)

Sets the mode of the analog value. Possible modes:

  • 0: Normal Mode (Analog value as set by analog_out_set_voltage() is applied)
  • 1: 1k Ohm resistor to ground
  • 2: 100k Ohm resistor to ground
  • 3: 500k Ohm resistor to ground

Setting the mode to 0 will result in an output voltage of 0. You can jump to a higher output voltage directly by calling analog_out_set_voltage().

The default mode is 1.

The following defines are available for this function:

  • ANALOG_OUT_MODE_ANALOG_VALUE = 0
  • ANALOG_OUT_MODE_1K_TO_GROUND = 1
  • ANALOG_OUT_MODE_100K_TO_GROUND = 2
  • ANALOG_OUT_MODE_500K_TO_GROUND = 3
int analog_out_get_mode(AnalogOut *analog_out, uint8_t *ret_mode)

Returns the mode as set by analog_out_set_mode().

The following defines are available for this function:

  • ANALOG_OUT_MODE_ANALOG_VALUE = 0
  • ANALOG_OUT_MODE_1K_TO_GROUND = 1
  • ANALOG_OUT_MODE_100K_TO_GROUND = 2
  • ANALOG_OUT_MODE_500K_TO_GROUND = 3

Advanced Functions

int analog_out_get_api_version(AnalogOut *analog_out, 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 analog_out_get_response_expected(AnalogOut *analog_out, 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 analog_out_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 analog_out_set_response_expected() for the list of function ID defines available for this function.

int analog_out_set_response_expected(AnalogOut *analog_out, 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:

  • ANALOG_OUT_FUNCTION_SET_VOLTAGE = 1
  • ANALOG_OUT_FUNCTION_SET_MODE = 3
int analog_out_set_response_expected_all(AnalogOut *analog_out, bool response_expected)

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

int analog_out_get_identity(AnalogOut *analog_out, 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.

Constants

ANALOG_OUT_DEVICE_IDENTIFIER

This constant is used to identify a Analog Out Bricklet.

The analog_out_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.

ANALOG_OUT_DEVICE_DISPLAY_NAME

This constant represents the human readable name of a Analog Out Bricklet.