This is the description of the C/C++ API bindings for the IO-4 Bricklet 2.0. General information and technical specifications for the IO-4 Bricklet 2.0 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_io4_v2.h"
#define HOST "localhost"
#define PORT 4223
#define UID "XYZ" // Change XYZ to the UID of your IO-4 Bricklet 2.0
int main(void) {
// Create IP connection
IPConnection ipcon;
ipcon_create(&ipcon);
// Create device object
IO4V2 io;
io4_v2_create(&io, 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 value
bool value[4];
if(io4_v2_get_value(&io, value) < 0) {
fprintf(stderr, "Could not get value, probably timeout\n");
return 1;
}
printf("Channel 0: %s\n", value[0] ? "true" : "false");
printf("Channel 1: %s\n", value[1] ? "true" : "false");
printf("Channel 2: %s\n", value[2] ? "true" : "false");
printf("Channel 3: %s\n", value[3] ? "true" : "false");
printf("Press key to exit\n");
getchar();
io4_v2_destroy(&io);
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 | #define IPCON_EXPOSE_MILLISLEEP
#include <stdio.h>
#include "ip_connection.h"
#include "bricklet_io4_v2.h"
#define HOST "localhost"
#define PORT 4223
#define UID "XYZ" // Change XYZ to the UID of your IO-4 Bricklet 2.0
int main(void) {
// Create IP connection
IPConnection ipcon;
ipcon_create(&ipcon);
// Create device object
IO4V2 io;
io4_v2_create(&io, 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
// Configure channel 3 as output low
io4_v2_set_configuration(&io, 3, 'o', false);
// Set channel 3 alternating high/low 10 times with 100 ms delay
int i;
for(i = 0; i < 10; ++i) {
millisleep(100);
io4_v2_set_selected_value(&io, 3, true);
millisleep(100);
io4_v2_set_selected_value(&io, 3, false);
}
printf("Press key to exit\n");
getchar();
io4_v2_destroy(&io);
ipcon_destroy(&ipcon); // Calls ipcon_disconnect internally
return 0;
}
|
Download (example_interrupt.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 | #include <stdio.h>
#include "ip_connection.h"
#include "bricklet_io4_v2.h"
#define HOST "localhost"
#define PORT 4223
#define UID "XYZ" // Change XYZ to the UID of your IO-4 Bricklet 2.0
// Callback function for input value callback
void cb_input_value(uint8_t channel, bool changed, bool value, void *user_data) {
(void)user_data; // avoid unused parameter warning
printf("Channel: %u\n", channel);
printf("Changed: %s\n", changed ? "true" : "false");
printf("Value: %s\n", value ? "true" : "false");
printf("\n");
}
int main(void) {
// Create IP connection
IPConnection ipcon;
ipcon_create(&ipcon);
// Create device object
IO4V2 io;
io4_v2_create(&io, 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 input value callback to function cb_input_value
io4_v2_register_callback(&io,
IO4_V2_CALLBACK_INPUT_VALUE,
(void (*)(void))cb_input_value,
NULL);
// Set period for input value (channel 1) callback to 0.5s (500ms)
io4_v2_set_input_value_callback_configuration(&io, 1, 500, false);
printf("Press key to exit\n");
getchar();
io4_v2_destroy(&io);
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.
io4_v2_create
(IO4V2 *io4_v2, const char *uid, IPConnection *ipcon)¶Parameters: |
|
---|
Creates the device object io4_v2
with the unique device ID uid
and adds
it to the IPConnection ipcon
:
IO4V2 io4_v2;
io4_v2_create(&io4_v2, "YOUR_DEVICE_UID", &ipcon);
This device object can be used after the IP connection has been connected.
io4_v2_destroy
(IO4V2 *io4_v2)¶Parameters: |
|
---|
Removes the device object io4_v2
from its IPConnection and destroys it.
The device object cannot be used anymore afterwards.
io4_v2_set_value
(IO4V2 *io4_v2, bool value[4])¶Parameters: |
|
---|---|
Returns: |
|
Sets the output value of all four channels. A value of true or false outputs logic 1 or logic 0 respectively on the corresponding channel.
Use io4_v2_set_selected_value()
to change only one output channel state.
For example: (True, True, False, False) will turn the channels 0-1 high and the channels 2-3 low.
All running monoflop timers and PWMs will be aborted if this function is called.
Note
This function does nothing for channels that are configured as input. Pull-up
resistors can be switched on with io4_v2_set_configuration()
.
io4_v2_get_value
(IO4V2 *io4_v2, bool ret_value[4])¶Parameters: |
|
---|---|
Output Parameters: |
|
Returns: |
|
Returns the logic levels that are currently measured on the channels. This function works if the channel is configured as input as well as if it is configured as output.
io4_v2_set_selected_value
(IO4V2 *io4_v2, uint8_t channel, bool value)¶Parameters: |
|
---|---|
Returns: |
|
Sets the output value of a specific channel without affecting the other channels.
A running monoflop timer or PWM for the specific channel will be aborted if this function is called.
Note
This function does nothing for channels that are configured as input. Pull-up
resistors can be switched on with io4_v2_set_configuration()
.
io4_v2_set_configuration
(IO4V2 *io4_v2, uint8_t channel, char direction, bool value)¶Parameters: |
|
---|---|
Returns: |
|
Configures the value and direction of a specific channel. Possible directions are 'i' and 'o' for input and output.
If the direction is configured as output, the value is either high or low (set as true or false).
If the direction is configured as input, the value is either pull-up or default (set as true or false).
For example:
A running monoflop timer or PWM for the specific channel will be aborted if this function is called.
The following constants are available for this function:
For direction:
io4_v2_get_configuration
(IO4V2 *io4_v2, uint8_t channel, char *ret_direction, bool *ret_value)¶Parameters: |
|
---|---|
Output Parameters: |
|
Returns: |
|
Returns the channel configuration as set by io4_v2_set_configuration()
.
The following constants are available for this function:
For ret_direction:
io4_v2_set_monoflop
(IO4V2 *io4_v2, uint8_t channel, bool value, uint32_t time)¶Parameters: |
|
---|---|
Returns: |
|
The first parameter is the desired state of the channel (true means output high and false means output low). The second parameter indicates the time that the channel should hold the state.
If this function is called with the parameters (true, 1500): The channel will turn on and in 1.5s it will turn off again.
A PWM for the selected channel will be aborted if this function is called.
A monoflop can be used as a failsafe mechanism. For example: Lets assume you have a RS485 bus and a IO-4 Bricklet 2.0 is connected to one of the slave stacks. You can now call this function every second, with a time parameter of two seconds. The channel will be high all the time. If now the RS485 connection is lost, the channel will turn low in at most two seconds.
io4_v2_get_monoflop
(IO4V2 *io4_v2, uint8_t channel, bool *ret_value, uint32_t *ret_time, uint32_t *ret_time_remaining)¶Parameters: |
|
---|---|
Output Parameters: |
|
Returns: |
|
Returns (for the given channel) the current value and the time as set by
io4_v2_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.
io4_v2_get_edge_count
(IO4V2 *io4_v2, uint8_t channel, bool reset_counter, uint32_t *ret_count)¶Parameters: |
|
---|---|
Output Parameters: |
|
Returns: |
|
Returns the current value of the edge counter for the selected channel. You can
configure the edges that are counted with io4_v2_set_edge_count_configuration()
.
If you set the reset counter to true, the count is set back to 0 directly after it is read.
Note
Calling this function is only allowed for channels configured as input.
io4_v2_set_edge_count_configuration
(IO4V2 *io4_v2, uint8_t channel, uint8_t edge_type, uint8_t debounce)¶Parameters: |
|
---|---|
Returns: |
|
Configures the edge counter for a specific channel.
The edge type parameter configures if rising edges, falling edges or both are counted if the channel is configured for input. Possible edge types are:
Configuring an edge counter resets its value to 0.
If you don't know what any of this means, just leave it at default. The default configuration is very likely OK for you.
Note
Calling this function is only allowed for channels configured as input.
The following constants are available for this function:
For edge_type:
io4_v2_get_edge_count_configuration
(IO4V2 *io4_v2, uint8_t channel, uint8_t *ret_edge_type, uint8_t *ret_debounce)¶Parameters: |
|
---|---|
Output Parameters: |
|
Returns: |
|
Returns the edge type and debounce time for the selected channel as set by
io4_v2_set_edge_count_configuration()
.
Note
Calling this function is only allowed for channels configured as input.
The following constants are available for this function:
For ret_edge_type:
io4_v2_set_pwm_configuration
(IO4V2 *io4_v2, uint8_t channel, uint32_t frequency, uint16_t duty_cycle)¶Parameters: |
|
---|---|
Returns: |
|
Activates a PWM for the given channel.
You need to set the channel to output before you call this function, otherwise it will
report an invalid parameter error. To turn the PWM off again, you can set the frequency to 0 or any other
function that changes a value of the channel (e.g. io4_v2_set_selected_value()
).
A running monoflop timer for the given channel will be aborted if this function is called.
io4_v2_get_pwm_configuration
(IO4V2 *io4_v2, uint8_t channel, uint32_t *ret_frequency, uint16_t *ret_duty_cycle)¶Parameters: |
|
---|---|
Output Parameters: |
|
Returns: |
|
Returns the PWM configuration as set by io4_v2_set_pwm_configuration()
.
io4_v2_get_spitfp_error_count
(IO4V2 *io4_v2, 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: |
|
---|---|
Output Parameters: |
|
Returns: |
|
Returns the error count for the communication between Brick and Bricklet.
The errors are divided into
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.
io4_v2_set_status_led_config
(IO4V2 *io4_v2, uint8_t config)¶Parameters: |
|
---|---|
Returns: |
|
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:
io4_v2_get_status_led_config
(IO4V2 *io4_v2, uint8_t *ret_config)¶Parameters: |
|
---|---|
Output Parameters: |
|
Returns: |
|
Returns the configuration as set by io4_v2_set_status_led_config()
The following constants are available for this function:
For ret_config:
io4_v2_get_chip_temperature
(IO4V2 *io4_v2, int16_t *ret_temperature)¶Parameters: |
|
---|---|
Output Parameters: |
|
Returns: |
|
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.
io4_v2_reset
(IO4V2 *io4_v2)¶Parameters: |
|
---|---|
Returns: |
|
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!
io4_v2_get_identity
(IO4V2 *io4_v2, 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.
io4_v2_register_callback
(IO4V2 *io4_v2, 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.
io4_v2_set_input_value_callback_configuration
(IO4V2 *io4_v2, uint8_t channel, uint32_t period, bool value_has_to_change)¶Parameters: |
|
---|---|
Returns: |
|
This callback can be configured per channel.
The period is the period with which the IO4_V2_CALLBACK_INPUT_VALUE
callback is triggered periodically. A value of 0 turns the callback off.
If the value has to change-parameter is set to true, the callback is only triggered after the value has changed. If the value didn't change within the period, the callback is triggered immediately on change.
If it is set to false, the callback is continuously triggered with the period, independent of the value.
io4_v2_get_input_value_callback_configuration
(IO4V2 *io4_v2, uint8_t channel, uint32_t *ret_period, bool *ret_value_has_to_change)¶Parameters: |
|
---|---|
Output Parameters: |
|
Returns: |
|
Returns the callback configuration for the given channel as set by
io4_v2_set_input_value_callback_configuration()
.
io4_v2_set_all_input_value_callback_configuration
(IO4V2 *io4_v2, uint32_t period, bool value_has_to_change)¶Parameters: |
|
---|---|
Returns: |
|
The period is the period with which the IO4_V2_CALLBACK_ALL_INPUT_VALUE
callback is triggered periodically. A value of 0 turns the callback off.
If the value has to change-parameter is set to true, the callback is only triggered after the value has changed. If the value didn't change within the period, the callback is triggered immediately on change.
If it is set to false, the callback is continuously triggered with the period, independent of the value.
io4_v2_get_all_input_value_callback_configuration
(IO4V2 *io4_v2, uint32_t *ret_period, bool *ret_value_has_to_change)¶Parameters: |
|
---|---|
Output Parameters: |
|
Returns: |
|
Returns the callback configuration as set by
io4_v2_set_all_input_value_callback_configuration()
.
Callbacks can be registered to receive time critical or recurring data from the
device. The registration is done with the io4_v2_register_callback()
function:
void my_callback(int value, void *user_data) { printf("Value: %d\n", value); } io4_v2_register_callback(&io4_v2, IO4_V2_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.
IO4_V2_CALLBACK_INPUT_VALUE
¶void callback(uint8_t channel, bool changed, bool value, void *user_data)
Callback Parameters: |
|
---|
This callback is triggered periodically according to the configuration set by
io4_v2_set_input_value_callback_configuration()
.
The parameters are the channel, a value-changed indicator and the actual value for the channel. The changed parameter is true if the value has changed since the last callback.
IO4_V2_CALLBACK_ALL_INPUT_VALUE
¶void callback(bool changed[4], bool value[4], void *user_data)
Callback Parameters: |
|
---|
This callback is triggered periodically according to the configuration set by
io4_v2_set_all_input_value_callback_configuration()
.
The parameters are the same as io4_v2_get_value()
. Additional the
changed parameter is true if the value has changed since
the last callback.
IO4_V2_CALLBACK_MONOFLOP_DONE
¶void callback(uint8_t channel, bool value, void *user_data)
Callback Parameters: |
|
---|
This callback is triggered whenever a monoflop timer reaches 0. The parameters contain the channel and the current value of the channel (the value after the monoflop).
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.
io4_v2_get_api_version
(IO4V2 *io4_v2, 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.
io4_v2_get_response_expected
(IO4V2 *io4_v2, 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
io4_v2_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:
io4_v2_set_response_expected
(IO4V2 *io4_v2, 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:
io4_v2_set_response_expected_all
(IO4V2 *io4_v2, bool response_expected)¶Parameters: |
|
---|---|
Returns: |
|
Changes the response expected flag for all setter and callback configuration functions of this device at once.
Internal functions are used for maintenance tasks such as flashing a new firmware of changing the UID of a Bricklet. These task should be performed using Brick Viewer instead of using the internal functions directly.
io4_v2_set_bootloader_mode
(IO4V2 *io4_v2, uint8_t mode, uint8_t *ret_status)¶Parameters: |
|
---|---|
Output Parameters: |
|
Returns: |
|
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:
For ret_status:
io4_v2_get_bootloader_mode
(IO4V2 *io4_v2, uint8_t *ret_mode)¶Parameters: |
|
---|---|
Output Parameters: |
|
Returns: |
|
Returns the current bootloader mode, see io4_v2_set_bootloader_mode()
.
The following constants are available for this function:
For ret_mode:
io4_v2_set_write_firmware_pointer
(IO4V2 *io4_v2, uint32_t pointer)¶Parameters: |
|
---|---|
Returns: |
|
Sets the firmware pointer for io4_v2_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.
io4_v2_write_firmware
(IO4V2 *io4_v2, uint8_t data[64], uint8_t *ret_status)¶Parameters: |
|
---|---|
Output Parameters: |
|
Returns: |
|
Writes 64 Bytes of firmware at the position as written by
io4_v2_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.
io4_v2_write_uid
(IO4V2 *io4_v2, uint32_t uid)¶Parameters: |
|
---|---|
Returns: |
|
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.
io4_v2_read_uid
(IO4V2 *io4_v2, uint32_t *ret_uid)¶Parameters: |
|
---|---|
Output Parameters: |
|
Returns: |
|
Returns the current UID as an integer. Encode as Base58 to get the usual string version.
IO4_V2_DEVICE_IDENTIFIER
¶This constant is used to identify a IO-4 Bricklet 2.0.
The io4_v2_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.
IO4_V2_DEVICE_DISPLAY_NAME
¶This constant represents the human readable name of a IO-4 Bricklet 2.0.