This is the description of the Perl API bindings for the Accelerometer Bricklet 2.0. General information and technical specifications for the Accelerometer Bricklet 2.0 are summarized in its hardware description.
An installation guide for the Perl 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 | #!/usr/bin/perl
use strict;
use Tinkerforge::IPConnection;
use Tinkerforge::BrickletAccelerometerV2;
use constant HOST => 'localhost';
use constant PORT => 4223;
use constant UID => 'XYZ'; # Change XYZ to the UID of your Accelerometer Bricklet 2.0
my $ipcon = Tinkerforge::IPConnection->new(); # Create IP connection
my $a = Tinkerforge::BrickletAccelerometerV2->new(&UID, $ipcon); # Create device object
$ipcon->connect(&HOST, &PORT); # Connect to brickd
# Don't use device before ipcon is connected
# Get current acceleration
my ($x, $y, $z) = $a->get_acceleration();
print "Acceleration [X]: " . $x/10000.0 . " g\n";
print "Acceleration [Y]: " . $y/10000.0 . " g\n";
print "Acceleration [Z]: " . $z/10000.0 . " g\n";
print "Press key to exit\n";
<STDIN>;
$ipcon->disconnect();
|
Download (example_callback.pl)
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 | #!/usr/bin/perl
use strict;
use Tinkerforge::IPConnection;
use Tinkerforge::BrickletAccelerometerV2;
use constant HOST => 'localhost';
use constant PORT => 4223;
use constant UID => 'XYZ'; # Change XYZ to the UID of your Accelerometer Bricklet 2.0
# Callback subroutine for acceleration callback
sub cb_acceleration
{
my ($x, $y, $z) = @_;
print "Acceleration [X]: " . $x/10000.0 . " g\n";
print "Acceleration [Y]: " . $y/10000.0 . " g\n";
print "Acceleration [Z]: " . $z/10000.0 . " g\n";
print "\n";
}
my $ipcon = Tinkerforge::IPConnection->new(); # Create IP connection
my $a = Tinkerforge::BrickletAccelerometerV2->new(&UID, $ipcon); # Create device object
$ipcon->connect(&HOST, &PORT); # Connect to brickd
# Don't use device before ipcon is connected
# Register acceleration callback to subroutine cb_acceleration
$a->register_callback($a->CALLBACK_ACCELERATION, 'cb_acceleration');
# Set period for acceleration callback to 1s (1000ms)
$a->set_acceleration_callback_configuration(1000, 0);
print "Press key to exit\n";
<STDIN>;
$ipcon->disconnect();
|
Generally, every subroutine of the Perl bindings can report an error as
Tinkerforge::Error
object via croak()
. The object has a
get_code()
and a get_message()
subroutine. There are different
error code:
All functions listed below are thread-safe.
BrickletAccelerometerV2
->
new
($uid, $ipcon)¶Parameters: |
|
---|---|
Returns: |
|
Creates an object with the unique device ID $uid
:
$accelerometer_v2 = BrickletAccelerometerV2->new("YOUR_DEVICE_UID", $ipcon);
This object can then be used after the IP Connection is connected.
BrickletAccelerometerV2
->
get_acceleration
()¶Return Array: |
|
---|
Returns the acceleration in x, y and z direction. The values
are given in gₙ/10000 (1gₙ = 9.80665m/s²). The range is
configured with set_configuration()
.
If you want to get the acceleration periodically, it is recommended
to use the CALLBACK_ACCELERATION
callback and set the period with
set_acceleration_callback_configuration()
.
BrickletAccelerometerV2
->
set_configuration
($data_rate, $full_scale)¶Parameters: |
|
---|---|
Returns: |
|
Configures the data rate and full scale range. Possible values are:
Decreasing data rate or full scale range will also decrease the noise on the data.
The following constants are available for this function:
For $data_rate:
For $full_scale:
BrickletAccelerometerV2
->
get_configuration
()¶Return Array: |
|
---|
Returns the configuration as set by set_configuration()
.
The following constants are available for this function:
For $data_rate:
For $full_scale:
BrickletAccelerometerV2
->
set_info_led_config
($config)¶Parameters: |
|
---|---|
Returns: |
|
Configures the info LED (marked as "Force" on the Bricklet) to be either turned off, turned on, or blink in heartbeat mode.
The following constants are available for this function:
For $config:
BrickletAccelerometerV2
->
get_info_led_config
()¶Returns: |
|
---|
Returns the LED configuration as set by set_info_led_config()
The following constants are available for this function:
For $config:
BrickletAccelerometerV2
->
set_filter_configuration
($iir_bypass, $low_pass_filter)¶Parameters: |
|
---|---|
Returns: |
|
Configures IIR Bypass filter mode and low pass filter roll off corner frequency.
The filter can be applied or bypassed and the corner frequency can be half or a ninth of the output data rate.
The following constants are available for this function:
For $iir_bypass:
For $low_pass_filter:
New in version 2.0.2 (Plugin).
BrickletAccelerometerV2
->
get_filter_configuration
()¶Return Array: |
|
---|
Returns the configuration as set by set_filter_configuration()
.
The following constants are available for this function:
For $iir_bypass:
For $low_pass_filter:
New in version 2.0.2 (Plugin).
BrickletAccelerometerV2
->
get_spitfp_error_count
()¶Return Array: |
|
---|
Returns the error count for the communication between Brick and Bricklet.
The errors are divided into
The errors counts are for errors that occur on the Bricklet side. All Bricks have a similar function that returns the errors on the Brick side.
BrickletAccelerometerV2
->
set_status_led_config
($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:
BrickletAccelerometerV2
->
get_status_led_config
()¶Returns: |
|
---|
Returns the configuration as set by set_status_led_config()
The following constants are available for this function:
For $config:
BrickletAccelerometerV2
->
get_chip_temperature
()¶Returns: |
|
---|
Returns the temperature as measured inside the microcontroller. The value returned is not the ambient temperature!
The temperature is only proportional to the real temperature and it has bad accuracy. Practically it is only useful as an indicator for temperature changes.
BrickletAccelerometerV2
->
reset
()¶Returns: |
|
---|
Calling this function will reset the Bricklet. All configurations will be lost.
After a reset you have to create new device objects, calling functions on the existing ones will result in undefined behavior!
BrickletAccelerometerV2
->
get_identity
()¶Return Array: |
|
---|
Returns the UID, the UID where the Bricklet is connected to, the position, the hardware and firmware version as well as the device identifier.
The position can be 'a', 'b', 'c', 'd', 'e', 'f', 'g' or 'h' (Bricklet Port). A Bricklet connected to an Isolator Bricklet is always at position 'z'.
The device identifier numbers can be found here. There is also a constant for the device identifier of this Bricklet.
BrickletAccelerometerV2
->
register_callback
($callback_id, $function)¶Parameters: |
|
---|---|
Returns: |
|
Registers the given $function
name with the given $callback_id
.
The available callback IDs with corresponding function signatures are listed below.
BrickletAccelerometerV2
->
set_acceleration_callback_configuration
($period, $value_has_to_change)¶Parameters: |
|
---|---|
Returns: |
|
The period is the period with which the CALLBACK_ACCELERATION
callback is triggered periodically. A value of 0 turns the callback off.
If the value has to change-parameter is set to true, the callback is only triggered after the value has changed. If the value didn't change within the period, the callback is triggered immediately on change.
If it is set to false, the callback is continuously triggered with the period, independent of the value.
If this callback is enabled, the CALLBACK_CONTINUOUS_ACCELERATION_16_BIT
callback
and CALLBACK_CONTINUOUS_ACCELERATION_8_BIT
callback will automatically be disabled.
BrickletAccelerometerV2
->
get_acceleration_callback_configuration
()¶Return Array: |
|
---|
Returns the callback configuration as set by
set_acceleration_callback_configuration()
.
BrickletAccelerometerV2
->
set_continuous_acceleration_configuration
($enable_x, $enable_y, $enable_z, $resolution)¶Parameters: |
|
---|---|
Returns: |
|
For high throughput of acceleration data (> 1000Hz) you have to use the
CALLBACK_CONTINUOUS_ACCELERATION_16_BIT
or CALLBACK_CONTINUOUS_ACCELERATION_8_BIT
callbacks.
You can enable the callback for each axis (x, y, z) individually and choose a resolution of 8 bit or 16 bit.
If at least one of the axis is enabled and the resolution is set to 8 bit,
the CALLBACK_CONTINUOUS_ACCELERATION_8_BIT
callback is activated. If at least
one of the axis is enabled and the resolution is set to 16 bit,
the CALLBACK_CONTINUOUS_ACCELERATION_16_BIT
callback is activated.
The returned values are raw ADC data. If you want to put this data into a FFT to determine the occurrences of specific frequencies we recommend that you use the data as is. It has all of the ADC noise in it. This noise looks like pure noise at first glance, but it might still have some frequnecy information in it that can be utilized by the FFT.
Otherwise you have to use the following formulas that depend on the configured
resolution (8/16 bit) and the full scale range (see set_configuration()
) to calculate
the data in gₙ/10000 (same unit that is returned by get_acceleration()
):
If a resolution of 8 bit is used, only the 8 most significant bits will be transferred, so you can use the following formulas:
If no axis is enabled, both callbacks are disabled. If one of the continuous
callbacks is enabled, the CALLBACK_ACCELERATION
callback is disabled.
The maximum throughput depends on the exact configuration:
Number of axis enabled | Throughput 8 bit | Throughout 16 bit |
---|---|---|
1 | 25600Hz | 25600Hz |
2 | 25600Hz | 15000Hz |
3 | 20000Hz | 10000Hz |
The following constants are available for this function:
For $resolution:
BrickletAccelerometerV2
->
get_continuous_acceleration_configuration
()¶Return Array: |
|
---|
Returns the continuous acceleration configuration as set by
set_continuous_acceleration_configuration()
.
The following constants are available for this function:
For $resolution:
Callbacks can be registered to receive
time critical or recurring data from the device. The registration is done
with the register_callback()
function of
the device object. The first parameter is the callback ID and the second
parameter the callback function name:
sub my_callback
{
print "@_[0]";
}
$accelerometer_v2->register_callback(BrickletAccelerometerV2->CALLBACK_EXAMPLE, 'my_callback')
The callback function will be called from an internal thread of the
IP Connection. In contrast to many other programming languages, variables are
not automatically shared between threads in Perl. If you want to share a global
variable between a callback function and the rest for your program it has to be
marked as :shared
. See the documentation of the threads::shared Perl module for more details.
The available constants with inherent number and type of parameters 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.
BrickletAccelerometerV2
->
CALLBACK_ACCELERATION
¶Callback Parameters: |
|
---|
This callback is triggered periodically according to the configuration set by
set_acceleration_callback_configuration()
.
The parameters are the same as get_acceleration()
.
BrickletAccelerometerV2
->
CALLBACK_CONTINUOUS_ACCELERATION_16_BIT
¶Callback Parameters: |
|
---|
Returns 30 acceleration values with 16 bit resolution. The data rate can
be configured with set_configuration()
and this callback can be
enabled with set_continuous_acceleration_configuration()
.
The returned values are raw ADC data. If you want to put this data into a FFT to determine the occurrences of specific frequencies we recommend that you use the data as is. It has all of the ADC noise in it. This noise looks like pure noise at first glance, but it might still have some frequnecy information in it that can be utilized by the FFT.
Otherwise you have to use the following formulas that depend on the
full scale range (see set_configuration()
) to calculate
the data in gₙ/10000 (same unit that is returned by get_acceleration()
):
The data is formated in the sequence "x, y, z, x, y, z, ..." depending on the enabled axis. Examples:
BrickletAccelerometerV2
->
CALLBACK_CONTINUOUS_ACCELERATION_8_BIT
¶Callback Parameters: |
|
---|
Returns 60 acceleration values with 8 bit resolution. The data rate can
be configured with set_configuration()
and this callback can be
enabled with set_continuous_acceleration_configuration()
.
The returned values are raw ADC data. If you want to put this data into a FFT to determine the occurrences of specific frequencies we recommend that you use the data as is. It has all of the ADC noise in it. This noise looks like pure noise at first glance, but it might still have some frequnecy information in it that can be utilized by the FFT.
Otherwise you have to use the following formulas that depend on the
full scale range (see set_configuration()
) to calculate
the data in gₙ/10000 (same unit that is returned by get_acceleration()
):
The data is formated in the sequence "x, y, z, x, y, z, ..." depending on the enabled axis. Examples:
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.
BrickletAccelerometerV2
->
get_api_version
()¶Return Array: |
|
---|
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.
BrickletAccelerometerV2
->
get_response_expected
($function_id)¶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
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 $function_id:
BrickletAccelerometerV2
->
set_response_expected
($function_id, $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 $function_id:
BrickletAccelerometerV2
->
set_response_expected_all
($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.
BrickletAccelerometerV2
->
set_bootloader_mode
($mode)¶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 $status:
BrickletAccelerometerV2
->
get_bootloader_mode
()¶Returns: |
|
---|
Returns the current bootloader mode, see set_bootloader_mode()
.
The following constants are available for this function:
For $mode:
BrickletAccelerometerV2
->
set_write_firmware_pointer
($pointer)¶Parameters: |
|
---|---|
Returns: |
|
Sets the firmware pointer for 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.
BrickletAccelerometerV2
->
write_firmware
(\@data)¶Parameters: |
|
---|---|
Returns: |
|
Writes 64 Bytes of firmware at the position as written by
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.
BrickletAccelerometerV2
->
write_uid
($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.
BrickletAccelerometerV2
->
read_uid
()¶Returns: |
|
---|
Returns the current UID as an integer. Encode as Base58 to get the usual string version.
BrickletAccelerometerV2
->
DEVICE_IDENTIFIER
¶This constant is used to identify a Accelerometer Bricklet 2.0.
The get_identity()
function and the
IPConnection->CALLBACK_ENUMERATE
callback of the IP Connection have a device_identifier
parameter to specify
the Brick's or Bricklet's type.
BrickletAccelerometerV2
->
DEVICE_DISPLAY_NAME
¶This constant represents the human readable name of a Accelerometer Bricklet 2.0.