PHP - Distance IR Bricklet 2.0

This is the description of the PHP API bindings for the Distance IR Bricklet 2.0. General information and technical specifications for the Distance IR Bricklet 2.0 are summarized in its hardware description.

An installation guide for the PHP API bindings is part of their general description.

Examples

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

Simple

Download (ExampleSimple.php)

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<?php

require_once('Tinkerforge/IPConnection.php');
require_once('Tinkerforge/BrickletDistanceIRV2.php');

use Tinkerforge\IPConnection;
use Tinkerforge\BrickletDistanceIRV2;

const HOST = 'localhost';
const PORT = 4223;
const UID = 'XYZ'; // Change XYZ to the UID of your Distance IR Bricklet 2.0

$ipcon = new IPConnection(); // Create IP connection
$dir = new BrickletDistanceIRV2(UID, $ipcon); // Create device object

$ipcon->connect(HOST, PORT); // Connect to brickd
// Don't use device before ipcon is connected

// Get current distance
$distance = $dir->getDistance();
echo "Distance: " . $distance/10.0 . " cm\n";

echo "Press key to exit\n";
fgetc(fopen('php://stdin', 'r'));
$ipcon->disconnect();

?>

Callback

Download (ExampleCallback.php)

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<?php

require_once('Tinkerforge/IPConnection.php');
require_once('Tinkerforge/BrickletDistanceIRV2.php');

use Tinkerforge\IPConnection;
use Tinkerforge\BrickletDistanceIRV2;

const HOST = 'localhost';
const PORT = 4223;
const UID = 'XYZ'; // Change XYZ to the UID of your Distance IR Bricklet 2.0

// Callback function for distance callback
function cb_distance($distance)
{
    echo "Distance: " . $distance/10.0 . " cm\n";
}

$ipcon = new IPConnection(); // Create IP connection
$dir = new BrickletDistanceIRV2(UID, $ipcon); // Create device object

$ipcon->connect(HOST, PORT); // Connect to brickd
// Don't use device before ipcon is connected

// Register distance callback to function cb_distance
$dir->registerCallback(BrickletDistanceIRV2::CALLBACK_DISTANCE, 'cb_distance');

// Set period for distance callback to 1s (1000ms) without a threshold
$dir->setDistanceCallbackConfiguration(1000, FALSE, 'x', 0, 0);

echo "Press ctrl+c to exit\n";
$ipcon->dispatchCallbacks(-1); // Dispatch callbacks forever

?>

Threshold

Download (ExampleThreshold.php)

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<?php

require_once('Tinkerforge/IPConnection.php');
require_once('Tinkerforge/BrickletDistanceIRV2.php');

use Tinkerforge\IPConnection;
use Tinkerforge\BrickletDistanceIRV2;

const HOST = 'localhost';
const PORT = 4223;
const UID = 'XYZ'; // Change XYZ to the UID of your Distance IR Bricklet 2.0

// Callback function for distance callback
function cb_distance($distance)
{
    echo "Distance: " . $distance/10.0 . " cm\n";
}

$ipcon = new IPConnection(); // Create IP connection
$dir = new BrickletDistanceIRV2(UID, $ipcon); // Create device object

$ipcon->connect(HOST, PORT); // Connect to brickd
// Don't use device before ipcon is connected

// Register distance callback to function cb_distance
$dir->registerCallback(BrickletDistanceIRV2::CALLBACK_DISTANCE, 'cb_distance');

// Configure threshold for distance "smaller than 30 cm"
// with a debounce period of 1s (1000ms)
$dir->setDistanceCallbackConfiguration(1000, FALSE, '<', 30*10, 0);

echo "Press ctrl+c to exit\n";
$ipcon->dispatchCallbacks(-1); // Dispatch callbacks forever

?>

API

Functions that return multiple values return them in an associative array.

Basic Functions

class BrickletDistanceIRV2(string $uid, IPConnection $ipcon)

Creates an object with the unique device ID $uid:

<?php   $distance_ir_v2 = new BrickletDistanceIRV2('YOUR_DEVICE_UID', $ipcon);   ?>

This object can then be used after the IP Connection is connected (see examples above).

int BrickletDistanceIRV2::getDistance()

Returns the distance measured by the sensor. The value is in mm and possible distance ranges are 40 to 300, 100 to 800 and 200 to 1500, depending on the selected IR sensor.

If you want to get the value periodically, it is recommended to use the CALLBACK_DISTANCE callback. You can set the callback configuration with setDistanceCallbackConfiguration().

int BrickletDistanceIRV2::getAnalogValue()

Returns the analog value as read by a analog-to-digital converter. The value has 21 bit with a range of 0 to 2097151.

This is unfiltered raw data. We made sure that the integration time of the ADC is shorter then the measurement interval of the sensor (10ms vs 16.5ms). So there is no information lost.

If you want to do your own calibration or create your own lookup table you can use this value.

If you want to get the value periodically, it is recommended to use the CALLBACK_ANALOG_VALUE callback. You can set the callback configuration with setAnalogValueCallbackConfiguration().

void BrickletDistanceIRV2::setMovingAverageConfiguration(int $moving_average_length)

Sets the length of a moving averaging for the resistance and temperature.

Setting the length to 1 will turn the averaging off. With less averaging, there is more noise on the data.

The range for the averaging is 1-1000.

New data is gathered every ~10ms. With a moving average of length 1000 the resulting averaging window has a length of approximately 10s. If you want to do long term measurements the longest moving average will give the cleanest results.

The default value is 25.

int BrickletDistanceIRV2::getMovingAverageConfiguration()

Returns the moving average configuration as set by setMovingAverageConfiguration().

void BrickletDistanceIRV2::setDistanceLEDConfig(int $config)

Configures the distance LED to be either turned off, turned on, blink in heartbeat mode or show the distance (brighter = object is nearer).

The default value is 3 (show distance).

The following constants are available for this function:

  • BrickletDistanceIRV2::DISTANCE_LED_CONFIG_OFF = 0
  • BrickletDistanceIRV2::DISTANCE_LED_CONFIG_ON = 1
  • BrickletDistanceIRV2::DISTANCE_LED_CONFIG_SHOW_HEARTBEAT = 2
  • BrickletDistanceIRV2::DISTANCE_LED_CONFIG_SHOW_DISTANCE = 3
int BrickletDistanceIRV2::getDistanceLEDConfig()

Returns the LED configuration as set by setDistanceLEDConfig()

The following constants are available for this function:

  • BrickletDistanceIRV2::DISTANCE_LED_CONFIG_OFF = 0
  • BrickletDistanceIRV2::DISTANCE_LED_CONFIG_ON = 1
  • BrickletDistanceIRV2::DISTANCE_LED_CONFIG_SHOW_HEARTBEAT = 2
  • BrickletDistanceIRV2::DISTANCE_LED_CONFIG_SHOW_DISTANCE = 3
void BrickletDistanceIRV2::setSensorType(int $sensor)

Sets the sensor type.

The Bricklet comes configured with the correct sensor type and the type is saved in flash (i.e. the Bricklet retains the information if power is lost).

If you want to change the sensor you can set the type in Brick Viewer, you will likely never need to call this function from your program.

The following constants are available for this function:

  • BrickletDistanceIRV2::SENSOR_TYPE_2Y0A41 = 0
  • BrickletDistanceIRV2::SENSOR_TYPE_2Y0A21 = 1
  • BrickletDistanceIRV2::SENSOR_TYPE_2Y0A02 = 2
int BrickletDistanceIRV2::getSensorType()

Returns the sensor type as set by setSensorType().

The following constants are available for this function:

  • BrickletDistanceIRV2::SENSOR_TYPE_2Y0A41 = 0
  • BrickletDistanceIRV2::SENSOR_TYPE_2Y0A21 = 1
  • BrickletDistanceIRV2::SENSOR_TYPE_2Y0A02 = 2

Advanced Functions

array BrickletDistanceIRV2::getAPIVersion()

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.

bool BrickletDistanceIRV2::getResponseExpected(int $function_id)

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 setResponseExpected(). 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 setResponseExpected() for the list of function ID constants available for this function.

void BrickletDistanceIRV2::setResponseExpected(int $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 constants are available for this function:

  • BrickletDistanceIRV2::FUNCTION_SET_DISTANCE_CALLBACK_CONFIGURATION = 2
  • BrickletDistanceIRV2::FUNCTION_SET_ANALOG_VALUE_CALLBACK_CONFIGURATION = 6
  • BrickletDistanceIRV2::FUNCTION_SET_MOVING_AVERAGE_CONFIGURATION = 9
  • BrickletDistanceIRV2::FUNCTION_SET_DISTANCE_LED_CONFIG = 11
  • BrickletDistanceIRV2::FUNCTION_SET_SENSOR_TYPE = 13
  • BrickletDistanceIRV2::FUNCTION_SET_WRITE_FIRMWARE_POINTER = 237
  • BrickletDistanceIRV2::FUNCTION_SET_STATUS_LED_CONFIG = 239
  • BrickletDistanceIRV2::FUNCTION_RESET = 243
  • BrickletDistanceIRV2::FUNCTION_WRITE_UID = 248
void BrickletDistanceIRV2::setResponseExpectedAll(bool $response_expected)

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

array BrickletDistanceIRV2::getSPITFPErrorCount()

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.

The returned array has the keys error_count_ack_checksum, error_count_message_checksum, error_count_frame and error_count_overflow.

int BrickletDistanceIRV2::setBootloaderMode(int $mode)

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:

  • BrickletDistanceIRV2::BOOTLOADER_MODE_BOOTLOADER = 0
  • BrickletDistanceIRV2::BOOTLOADER_MODE_FIRMWARE = 1
  • BrickletDistanceIRV2::BOOTLOADER_MODE_BOOTLOADER_WAIT_FOR_REBOOT = 2
  • BrickletDistanceIRV2::BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_REBOOT = 3
  • BrickletDistanceIRV2::BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_ERASE_AND_REBOOT = 4
  • BrickletDistanceIRV2::BOOTLOADER_STATUS_OK = 0
  • BrickletDistanceIRV2::BOOTLOADER_STATUS_INVALID_MODE = 1
  • BrickletDistanceIRV2::BOOTLOADER_STATUS_NO_CHANGE = 2
  • BrickletDistanceIRV2::BOOTLOADER_STATUS_ENTRY_FUNCTION_NOT_PRESENT = 3
  • BrickletDistanceIRV2::BOOTLOADER_STATUS_DEVICE_IDENTIFIER_INCORRECT = 4
  • BrickletDistanceIRV2::BOOTLOADER_STATUS_CRC_MISMATCH = 5
int BrickletDistanceIRV2::getBootloaderMode()

Returns the current bootloader mode, see setBootloaderMode().

The following constants are available for this function:

  • BrickletDistanceIRV2::BOOTLOADER_MODE_BOOTLOADER = 0
  • BrickletDistanceIRV2::BOOTLOADER_MODE_FIRMWARE = 1
  • BrickletDistanceIRV2::BOOTLOADER_MODE_BOOTLOADER_WAIT_FOR_REBOOT = 2
  • BrickletDistanceIRV2::BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_REBOOT = 3
  • BrickletDistanceIRV2::BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_ERASE_AND_REBOOT = 4
void BrickletDistanceIRV2::setWriteFirmwarePointer(int $pointer)

Sets the firmware pointer for writeFirmware(). 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 BrickletDistanceIRV2::writeFirmware(array $data)

Writes 64 Bytes of firmware at the position as written by setWriteFirmwarePointer() 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.

void BrickletDistanceIRV2::setStatusLEDConfig(int $config)

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:

  • BrickletDistanceIRV2::STATUS_LED_CONFIG_OFF = 0
  • BrickletDistanceIRV2::STATUS_LED_CONFIG_ON = 1
  • BrickletDistanceIRV2::STATUS_LED_CONFIG_SHOW_HEARTBEAT = 2
  • BrickletDistanceIRV2::STATUS_LED_CONFIG_SHOW_STATUS = 3
int BrickletDistanceIRV2::getStatusLEDConfig()

Returns the configuration as set by setStatusLEDConfig()

The following constants are available for this function:

  • BrickletDistanceIRV2::STATUS_LED_CONFIG_OFF = 0
  • BrickletDistanceIRV2::STATUS_LED_CONFIG_ON = 1
  • BrickletDistanceIRV2::STATUS_LED_CONFIG_SHOW_HEARTBEAT = 2
  • BrickletDistanceIRV2::STATUS_LED_CONFIG_SHOW_STATUS = 3
int BrickletDistanceIRV2::getChipTemperature()

Returns the temperature in °C 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.

void BrickletDistanceIRV2::reset()

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!

void BrickletDistanceIRV2::writeUID(int $uid)

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 BrickletDistanceIRV2::readUID()

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

array BrickletDistanceIRV2::getIdentity()

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.

The returned array has the keys uid, connected_uid, position, hardware_version, firmware_version and device_identifier.

Callback Configuration Functions

void BrickletDistanceIRV2::registerCallback(int $callback_id, callable $callback, mixed $user_data=NULL)

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

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

void BrickletDistanceIRV2::setDistanceCallbackConfiguration(int $period, bool $value_has_to_change, string $option, int $min, int $max)

The period in ms is the period with which the CALLBACK_DISTANCE 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.

It is furthermore possible to constrain the callback with thresholds.

The option-parameter together with min/max sets a threshold for the CALLBACK_DISTANCE callback.

The following options are possible:

Option Description
'x' Threshold is turned off
'o' Threshold is triggered when the value is outside the min and max values
'i' Threshold is triggered when the value is inside or equal to the min and max values
'<' Threshold is triggered when the value is smaller than the min value (max is ignored)
'>' Threshold is triggered when the value is greater than the min value (max is ignored)

If the option is set to 'x' (threshold turned off) the callback is triggered with the fixed period.

The default value is (0, false, 'x', 0, 0).

The following constants are available for this function:

  • BrickletDistanceIRV2::THRESHOLD_OPTION_OFF = 'x'
  • BrickletDistanceIRV2::THRESHOLD_OPTION_OUTSIDE = 'o'
  • BrickletDistanceIRV2::THRESHOLD_OPTION_INSIDE = 'i'
  • BrickletDistanceIRV2::THRESHOLD_OPTION_SMALLER = '<'
  • BrickletDistanceIRV2::THRESHOLD_OPTION_GREATER = '>'
array BrickletDistanceIRV2::getDistanceCallbackConfiguration()

Returns the callback configuration as set by setDistanceCallbackConfiguration().

The following constants are available for this function:

  • BrickletDistanceIRV2::THRESHOLD_OPTION_OFF = 'x'
  • BrickletDistanceIRV2::THRESHOLD_OPTION_OUTSIDE = 'o'
  • BrickletDistanceIRV2::THRESHOLD_OPTION_INSIDE = 'i'
  • BrickletDistanceIRV2::THRESHOLD_OPTION_SMALLER = '<'
  • BrickletDistanceIRV2::THRESHOLD_OPTION_GREATER = '>'

The returned array has the keys period, value_has_to_change, option, min and max.

void BrickletDistanceIRV2::setAnalogValueCallbackConfiguration(int $period, bool $value_has_to_change, string $option, int $min, int $max)

The period in ms is the period with which the CALLBACK_ANALOG_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.

It is furthermore possible to constrain the callback with thresholds.

The option-parameter together with min/max sets a threshold for the CALLBACK_ANALOG_VALUE callback.

The following options are possible:

Option Description
'x' Threshold is turned off
'o' Threshold is triggered when the value is outside the min and max values
'i' Threshold is triggered when the value is inside or equal to the min and max values
'<' Threshold is triggered when the value is smaller than the min value (max is ignored)
'>' Threshold is triggered when the value is greater than the min value (max is ignored)

If the option is set to 'x' (threshold turned off) the callback is triggered with the fixed period.

The default value is (0, false, 'x', 0, 0).

The following constants are available for this function:

  • BrickletDistanceIRV2::THRESHOLD_OPTION_OFF = 'x'
  • BrickletDistanceIRV2::THRESHOLD_OPTION_OUTSIDE = 'o'
  • BrickletDistanceIRV2::THRESHOLD_OPTION_INSIDE = 'i'
  • BrickletDistanceIRV2::THRESHOLD_OPTION_SMALLER = '<'
  • BrickletDistanceIRV2::THRESHOLD_OPTION_GREATER = '>'
array BrickletDistanceIRV2::getAnalogValueCallbackConfiguration()

Returns the callback configuration as set by setAnalogValueCallbackConfiguration().

The following constants are available for this function:

  • BrickletDistanceIRV2::THRESHOLD_OPTION_OFF = 'x'
  • BrickletDistanceIRV2::THRESHOLD_OPTION_OUTSIDE = 'o'
  • BrickletDistanceIRV2::THRESHOLD_OPTION_INSIDE = 'i'
  • BrickletDistanceIRV2::THRESHOLD_OPTION_SMALLER = '<'
  • BrickletDistanceIRV2::THRESHOLD_OPTION_GREATER = '>'

The returned array has the keys period, value_has_to_change, option, min and max.

Callbacks

Callbacks can be registered to receive time critical or recurring data from the device. The registration is done with the registerCallback() function of the device object. The first parameter is the callback ID and the second parameter the callback function:

<?php

function myCallback($param)
{
    echo $param . "\n";
}

$distance_ir_v2->registerCallback(BrickletDistanceIRV2::CALLBACK_EXAMPLE, 'myCallback');

?>

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.

int BrickletDistanceIRV2::CALLBACK_DISTANCE
<?php   void callback(int $distance [, mixed $user_data])   ?>

This callback is triggered periodically according to the configuration set by setDistanceCallbackConfiguration().

The parameter is the same as getDistance().

int BrickletDistanceIRV2::CALLBACK_ANALOG_VALUE
<?php   void callback(int $analog_value [, mixed $user_data])   ?>

This callback is triggered periodically according to the configuration set by setAnalogValueCallbackConfiguration().

The parameter is the same as getAnalogValue().

Constants

int BrickletDistanceIRV2::DEVICE_IDENTIFIER

This constant is used to identify a Distance IR Bricklet 2.0.

The getIdentity() function and the CALLBACK_ENUMERATE callback of the IP Connection have a deviceIdentifier parameter to specify the Brick's or Bricklet's type.

string BrickletDistanceIRV2::DEVICE_DISPLAY_NAME

This constant represents the human readable name of a Distance IR Bricklet 2.0.