This is the description of the C/C++ API bindings for the Color Bricklet. General information and technical specifications for the Color Bricklet are summarized in its hardware description.
An installation guide for the C/C++ API bindings is part of their general description.
The example code below is Public Domain (CC0 1.0).
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 | #include <stdio.h>
#include "ip_connection.h"
#include "bricklet_color.h"
#define HOST "localhost"
#define PORT 4223
#define UID "XYZ" // Change XYZ to the UID of your Color Bricklet
int main(void) {
// Create IP connection
IPConnection ipcon;
ipcon_create(&ipcon);
// Create device object
Color c;
color_create(&c, 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
// Get current color
uint16_t r, g, b, c_;
if(color_get_color(&c, &r, &g, &b, &c_) < 0) {
fprintf(stderr, "Could not get color, probably timeout\n");
return 1;
}
printf("Color [R]: %u\n", r);
printf("Color [G]: %u\n", g);
printf("Color [B]: %u\n", b);
printf("Color [C]: %u\n", c_);
printf("Press key to exit\n");
getchar();
color_destroy(&c);
ipcon_destroy(&ipcon); // Calls ipcon_disconnect internally
return 0;
}
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 | #include <stdio.h>
#include "ip_connection.h"
#include "bricklet_color.h"
#define HOST "localhost"
#define PORT 4223
#define UID "XYZ" // Change XYZ to the UID of your Color Bricklet
// Callback function for color callback
void cb_color(uint16_t r, uint16_t g, uint16_t b, uint16_t c, void *user_data) {
(void)user_data; // avoid unused parameter warning
printf("Color [R]: %u\n", r);
printf("Color [G]: %u\n", g);
printf("Color [B]: %u\n", b);
printf("Color [C]: %u\n", c);
printf("\n");
}
int main(void) {
// Create IP connection
IPConnection ipcon;
ipcon_create(&ipcon);
// Create device object
Color c;
color_create(&c, 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
// Register color callback to function cb_color
color_register_callback(&c,
COLOR_CALLBACK_COLOR,
(void (*)(void))cb_color,
NULL);
// Set period for color callback to 1s (1000ms)
// Note: The color callback is only called every second
// if the color has changed since the last call!
color_set_color_callback_period(&c, 1000);
printf("Press key to exit\n");
getchar();
color_destroy(&c);
ipcon_destroy(&ipcon); // Calls ipcon_disconnect internally
return 0;
}
|
Download (example_threshold.c)
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 | #include <stdio.h>
#include "ip_connection.h"
#include "bricklet_color.h"
#define HOST "localhost"
#define PORT 4223
#define UID "XYZ" // Change XYZ to the UID of your Color Bricklet
// Callback function for color reached callback
void cb_color_reached(uint16_t r, uint16_t g, uint16_t b, uint16_t c, void *user_data) {
(void)user_data; // avoid unused parameter warning
printf("Color [R]: %u\n", r);
printf("Color [G]: %u\n", g);
printf("Color [B]: %u\n", b);
printf("Color [C]: %u\n", c);
printf("\n");
}
int main(void) {
// Create IP connection
IPConnection ipcon;
ipcon_create(&ipcon);
// Create device object
Color c;
color_create(&c, 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
// Get threshold callbacks with a debounce time of 10 seconds (10000ms)
color_set_debounce_period(&c, 10000);
// Register color reached callback to function cb_color_reached
color_register_callback(&c,
COLOR_CALLBACK_COLOR_REACHED,
(void (*)(void))cb_color_reached,
NULL);
// Configure threshold for color "greater than 100, 200, 300, 400"
color_set_color_callback_threshold(&c, '>', 100, 0, 200, 0, 300, 0, 400, 0);
printf("Press key to exit\n");
getchar();
color_destroy(&c);
ipcon_destroy(&ipcon); // Calls ipcon_disconnect internally
return 0;
}
|
Most functions of the C/C++ bindings return an error code (e_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:
as defined in ip_connection.h
.
All functions listed below are thread-safe.
color_create
(Color *color, const char *uid, IPConnection *ipcon)¶Parameters: |
|
---|
Creates the device object color
with the unique device ID uid
and adds
it to the IPConnection ipcon
:
Color color;
color_create(&color, "YOUR_DEVICE_UID", &ipcon);
This device object can be used after the IP connection has been connected.
color_destroy
(Color *color)¶Parameters: |
|
---|
Removes the device object color
from its IPConnection and destroys it.
The device object cannot be used anymore afterwards.
color_get_color
(Color *color, uint16_t *ret_r, uint16_t *ret_g, uint16_t *ret_b, uint16_t *ret_c)¶Parameters: |
|
---|---|
Output Parameters: |
|
Returns: |
|
Returns the measured color of the sensor.
The red (r), green (g), blue (b) and clear (c) colors are measured with four different photodiodes that are responsive at different wavelengths:
If you want to get the color periodically, it is recommended
to use the COLOR_CALLBACK_COLOR
callback and set the period with
color_set_color_callback_period()
.
color_light_on
(Color *color)¶Parameters: |
|
---|---|
Returns: |
|
Turns the LED on.
color_light_off
(Color *color)¶Parameters: |
|
---|---|
Returns: |
|
Turns the LED off.
color_is_light_on
(Color *color, uint8_t *ret_light)¶Parameters: |
|
---|---|
Output Parameters: |
|
Returns: |
|
Returns the state of the LED. Possible values are:
The following constants are available for this function:
For ret_light:
color_set_config
(Color *color, uint8_t gain, uint8_t integration_time)¶Parameters: |
|
---|---|
Returns: |
|
Sets the configuration of the sensor. Gain and integration time can be configured in this way.
For configuring the gain:
For configuring the integration time:
Increasing the gain enables the sensor to detect a color from a higher distance.
The integration time provides a trade-off between conversion time and accuracy. With a longer integration time the values read will be more accurate but it will take longer time to get the conversion results.
The following constants are available for this function:
For gain:
For integration_time:
color_get_config
(Color *color, uint8_t *ret_gain, uint8_t *ret_integration_time)¶Parameters: |
|
---|---|
Output Parameters: |
|
Returns: |
|
Returns the configuration as set by color_set_config()
.
The following constants are available for this function:
For ret_gain:
For ret_integration_time:
color_get_illuminance
(Color *color, uint32_t *ret_illuminance)¶Parameters: |
|
---|---|
Output Parameters: |
|
Returns: |
|
Returns the illuminance affected by the gain and integration time as
set by color_set_config()
. To get the illuminance in Lux apply this formula:
lux = illuminance * 700 / gain / integration_time
To get a correct illuminance measurement make sure that the color
values themselves are not saturated. The color value (R, G or B)
is saturated if it is equal to the maximum value of 65535.
In that case you have to reduce the gain, see color_set_config()
.
color_get_color_temperature
(Color *color, uint16_t *ret_color_temperature)¶Parameters: |
|
---|---|
Output Parameters: |
|
Returns: |
|
Returns the color temperature.
To get a correct color temperature measurement make sure that the color
values themselves are not saturated. The color value (R, G or B)
is saturated if it is equal to the maximum value of 65535.
In that case you have to reduce the gain, see color_set_config()
.
color_get_identity
(Color *color, 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: |
|
---|---|
Output Parameters: |
|
Returns: |
|
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). A Bricklet connected to an Isolator Bricklet is always at position 'z'.
The device identifier numbers can be found here. There is also a constant for the device identifier of this Bricklet.
color_register_callback
(Color *color, int16_t callback_id, void (*function)(void), void *user_data)¶Parameters: |
|
---|
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.
color_set_color_callback_period
(Color *color, uint32_t period)¶Parameters: |
|
---|---|
Returns: |
|
Sets the period with which the COLOR_CALLBACK_COLOR
callback is triggered
periodically. A value of 0 turns the callback off.
The COLOR_CALLBACK_COLOR
callback is only triggered if the color has changed since the
last triggering.
color_get_color_callback_period
(Color *color, uint32_t *ret_period)¶Parameters: |
|
---|---|
Output Parameters: |
|
Returns: |
|
Returns the period as set by color_set_color_callback_period()
.
color_set_color_callback_threshold
(Color *color, char option, uint16_t min_r, uint16_t max_r, uint16_t min_g, uint16_t max_g, uint16_t min_b, uint16_t max_b, uint16_t min_c, uint16_t max_c)¶Parameters: |
|
---|---|
Returns: |
|
Sets the thresholds for the COLOR_CALLBACK_COLOR_REACHED
callback.
The following options are possible:
Option | Description |
---|---|
'x' | Callback is turned off |
'o' | Callback is triggered when the temperature is outside the min and max values |
'i' | Callback is triggered when the temperature is inside the min and max values |
'<' | Callback is triggered when the temperature is smaller than the min value (max is ignored) |
'>' | Callback is triggered when the temperature is greater than the min value (max is ignored) |
The following constants are available for this function:
For option:
color_get_color_callback_threshold
(Color *color, char *ret_option, uint16_t *ret_min_r, uint16_t *ret_max_r, uint16_t *ret_min_g, uint16_t *ret_max_g, uint16_t *ret_min_b, uint16_t *ret_max_b, uint16_t *ret_min_c, uint16_t *ret_max_c)¶Parameters: |
|
---|---|
Output Parameters: |
|
Returns: |
|
Returns the threshold as set by color_set_color_callback_threshold()
.
The following constants are available for this function:
For ret_option:
color_set_debounce_period
(Color *color, uint32_t debounce)¶Parameters: |
|
---|---|
Returns: |
|
Sets the period with which the threshold callback
is triggered, if the threshold
keeps being reached.
color_get_debounce_period
(Color *color, uint32_t *ret_debounce)¶Parameters: |
|
---|---|
Output Parameters: |
|
Returns: |
|
Returns the debounce period as set by color_set_debounce_period()
.
color_set_illuminance_callback_period
(Color *color, uint32_t period)¶Parameters: |
|
---|---|
Returns: |
|
Sets the period with which the COLOR_CALLBACK_ILLUMINANCE
callback is triggered
periodically. A value of 0 turns the callback off.
The COLOR_CALLBACK_ILLUMINANCE
callback is only triggered if the illuminance has changed
since the last triggering.
color_get_illuminance_callback_period
(Color *color, uint32_t *ret_period)¶Parameters: |
|
---|---|
Output Parameters: |
|
Returns: |
|
Returns the period as set by color_set_illuminance_callback_period()
.
color_set_color_temperature_callback_period
(Color *color, uint32_t period)¶Parameters: |
|
---|---|
Returns: |
|
Sets the period with which the COLOR_CALLBACK_COLOR_TEMPERATURE
callback is
triggered periodically. A value of 0 turns the callback off.
The COLOR_CALLBACK_COLOR_TEMPERATURE
callback is only triggered if the color temperature
has changed since the last triggering.
color_get_color_temperature_callback_period
(Color *color, uint32_t *ret_period)¶Parameters: |
|
---|---|
Output Parameters: |
|
Returns: |
|
Returns the period as set by color_set_color_temperature_callback_period()
.
Callbacks can be registered to receive time critical or recurring data from the
device. The registration is done with the color_register_callback()
function:
void my_callback(int value, void *user_data) { printf("Value: %d\n", value); } color_register_callback(&color, COLOR_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.
COLOR_CALLBACK_COLOR
¶void callback(uint16_t r, uint16_t g, uint16_t b, uint16_t c, void *user_data)
Callback Parameters: |
|
---|
This callback is triggered periodically with the period that is set by
color_set_color_callback_period()
. The parameter is the color
of the sensor as RGBC.
The COLOR_CALLBACK_COLOR
callback is only triggered if the color has changed since the
last triggering.
COLOR_CALLBACK_COLOR_REACHED
¶void callback(uint16_t r, uint16_t g, uint16_t b, uint16_t c, void *user_data)
Callback Parameters: |
|
---|
This callback is triggered when the threshold as set by
color_set_color_callback_threshold()
is reached.
The parameter is the color
of the sensor as RGBC.
If the threshold keeps being reached, the callback is triggered periodically
with the period as set by color_set_debounce_period()
.
COLOR_CALLBACK_ILLUMINANCE
¶void callback(uint32_t illuminance, void *user_data)
Callback Parameters: |
|
---|
This callback is triggered periodically with the period that is set by
color_set_illuminance_callback_period()
. The parameter is the illuminance.
See color_get_illuminance()
for how to interpret this value.
The COLOR_CALLBACK_ILLUMINANCE
callback is only triggered if the illuminance has changed
since the last triggering.
COLOR_CALLBACK_COLOR_TEMPERATURE
¶void callback(uint16_t color_temperature, void *user_data)
Callback Parameters: |
|
---|
This callback is triggered periodically with the period that is set by
color_set_color_temperature_callback_period()
. The parameter is the
color temperature.
The COLOR_CALLBACK_COLOR_TEMPERATURE
callback is only triggered if the color temperature
has changed since the last triggering.
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.
color_get_api_version
(Color *color, uint8_t ret_api_version[3])¶Parameters: |
|
---|---|
Output Parameters: |
|
Returns: |
|
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.
color_get_response_expected
(Color *color, uint8_t function_id, bool *ret_response_expected)¶Parameters: |
|
---|---|
Output Parameters: |
|
Returns: |
|
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
color_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 sent and errors are silently ignored, because they cannot be detected.
The following constants are available for this function:
For function_id:
color_set_response_expected
(Color *color, uint8_t function_id, bool response_expected)¶Parameters: |
|
---|---|
Returns: |
|
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 sent and errors are silently ignored, because they cannot be detected.
The following constants are available for this function:
For function_id:
color_set_response_expected_all
(Color *color, bool response_expected)¶Parameters: |
|
---|---|
Returns: |
|
Changes the response expected flag for all setter and callback configuration functions of this device at once.
COLOR_DEVICE_IDENTIFIER
¶This constant is used to identify a Color Bricklet.
The color_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.
COLOR_DEVICE_DISPLAY_NAME
¶This constant represents the human readable name of a Color Bricklet.