This is the description of the Python API bindings for the Industrial Digital In 4 Bricklet. General information and technical specifications for the Industrial Digital In 4 Bricklet are summarized in its hardware description.
An installation guide for the Python 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 | #!/usr/bin/env python
# -*- coding: utf-8 -*-
HOST = "localhost"
PORT = 4223
UID = "xyz" # Change to your UID
import time
from tinkerforge.ip_connection import IPConnection
from tinkerforge.bricklet_industrial_digital_in_4 import IndustrialDigitalIn4
if __name__ == "__main__":
ipcon = IPConnection() # Create IP connection
idi4 = IndustrialDigitalIn4(UID, ipcon) # Create device object
ipcon.connect(HOST, PORT) # Connect to brickd
# Don't use device before ipcon is connected
# Read out values as bitmask
value = idi4.get_value()
print('Value: ' + str(bin(value)))
raw_input('Press key to exit\n') # Use input() in Python 3
ipcon.disconnect()
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Download (example_interrupt.py)
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 | #!/usr/bin/env python
# -*- coding: utf-8 -*-
HOST = "localhost"
PORT = 4223
UID = "xyz" # Change to your UID
from tinkerforge.ip_connection import IPConnection
from tinkerforge.bricklet_industrial_digital_in_4 import IndustrialDigitalIn4
# Callback function for interrupts
def cb_interrupt(interrupt_mask, value_mask):
print('Interrupt by: ' + str(bin(interrupt_mask)))
print('Value: ' + str(bin(value_mask)))
if __name__ == "__main__":
ipcon = IPConnection() # Create IP connection
idi4 = IndustrialDigitalIn4(UID, ipcon) # Create device object
ipcon.connect(HOST, PORT) # Connect to brickd
# Don't use device before ipcon is connected
# Register callback for interrupts
idi4.register_callback(idi4.CALLBACK_INTERRUPT, cb_interrupt)
# Enable interrupt on pin 0
idi4.set_interrupt(1 << 0)
raw_input('Press key to exit\n') # Use input() in Python 3
ipcon.disconnect()
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Generally, every method of the Python bindings can throw an tinkerforge.ip_connection.Error exception that has a value and a description property. value can have different values:
All methods listed below are thread-safe.
Parameters: |
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Creates an object with the unique device ID uid:
industrial_digital_in_4 = IndustrialDigitalIn4("YOUR_DEVICE_UID", ipcon)
This object can then be used after the IP Connection is connected (see examples above).
Return type: | int |
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Returns the input value with a bitmask. The bitmask is 16bit long, true refers to high and false refers to low.
For example: The value 3 or 0b0011 means that pins 0-1 are high and the other pins are low.
If no groups are used (see set_group()), the pins correspond to the markings on the Digital In 4 Bricklet.
If groups are used, the pins correspond to the element in the group. Element 1 in the group will get pins 0-3, element 2 pins 4-7, element 3 pins 8-11 and element 4 pins 12-15.
Parameters: |
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Return type: | int |
Returns the current value of the edge counter for the selected pin. You can configure the edges that are counted with set_edge_count_config().
If you set the reset counter to true, the count is set back to 0 directly after it is read.
New in version 2.0.1 (Plugin).
Parameters: | group -- [chr, chr, chr, chr] |
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Return type: | None |
Sets a group of Digital In 4 Bricklets that should work together. You can find Bricklets that can be grouped together with get_available_for_group().
The group consists of 4 elements. Element 1 in the group will get pins 0-3, element 2 pins 4-7, element 3 pins 8-11 and element 4 pins 12-15.
Each element can either be one of the ports ('a' to 'd') or 'n' if it should not be used.
For example: If you have two Digital In 4 Bricklets connected to port A and port B respectively, you could call with ['a', 'b', 'n', 'n'].
Now the pins on the Digital In 4 on port A are assigned to 0-3 and the pins on the Digital In 4 on port B are assigned to 4-7. It is now possible to call get_value() and read out two Bricklets at the same time.
Changing the group configuration resets all edge counter configurations and values.
Return type: | [chr, chr, chr, chr] |
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Returns the group as set by set_group()
Return type: | int |
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Returns a bitmask of ports that are available for grouping. For example the value 5 or 0b0101 means: Port A and port C are connected to Bricklets that can be grouped together.
Parameters: |
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Return type: | None |
Configures the edge counter for the selected pins. A bitmask of 9 or 0b1001 will enable the edge counter for pins 0 and 3.
The edge type parameter configures if rising edges, falling edges or both are counted if the pin is configured for input. Possible edge types are:
The debounce time is given in ms.
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.
Default values: 0 (edge type) and 100ms (debounce time)
The following constants are available for this function:
New in version 2.0.1 (Plugin).
Parameters: | pin -- int |
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Return type: | (int, int) |
Returns the edge type and debounce time for the selected pin as set by set_edge_count_config().
The following constants are available for this function:
New in version 2.0.1 (Plugin).
The returned namedtuple has the variables edge_type and debounce.
Return type: | [int, int, int] |
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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.
Parameters: | function_id -- int |
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Return type: | bool |
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 send and errors are silently ignored, because they cannot be detected.
See set_response_expected() for the list of function ID constants available for this function.
Parameters: |
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Return type: | None |
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 and callbacks it is always disabled.
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:
Parameters: | response_expected -- bool |
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Return type: | None |
Changes the response expected flag for all setter and callback configuration functions of this device at once.
Return type: | (str, str, chr, [int, int, int], [int, int, int], int) |
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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 namedtuple has the variables uid, connected_uid, position, hardware_version, firmware_version and device_identifier.
Parameters: |
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Return type: | None |
Registers a callback with ID id to the function callback. The available IDs with corresponding function signatures are listed below.
Parameters: | debounce -- int |
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Return type: | None |
Sets the debounce period of the CALLBACK_INTERRUPT callback in ms.
For example: If you set this value to 100, you will get the interrupt maximal every 100ms. This is necessary if something that bounces is connected to the Digital In 4 Bricklet, such as a button.
The default value is 100.
Return type: | int |
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Returns the debounce period as set by set_debounce_period().
Parameters: | interrupt_mask -- int |
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Return type: | None |
Sets the pins on which an interrupt is activated with a bitmask. Interrupts are triggered on changes of the voltage level of the pin, i.e. changes from high to low and low to high.
For example: An interrupt bitmask of 9 or 0b1001 will enable the interrupt for pins 0 and 3.
The interrupts use the grouping as set by set_group().
The interrupt is delivered with the callback CALLBACK_INTERRUPT.
Return type: | int |
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Returns the interrupt bitmask as set by set_interrupt().
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:
def my_callback(param):
print(param)
industrial_digital_in_4.register_callback(IndustrialDigitalIn4.CALLBACK_EXAMPLE, my_callback)
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.
Parameters: |
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This callback is triggered whenever a change of the voltage level is detected on pins where the interrupt was activated with set_interrupt().
The values are a bitmask that specifies which interrupts occurred and the current value bitmask.
For example:
This constant is used to identify a Industrial Digital In 4 Bricklet.
The get_identity() function and the CALLBACK_ENUMERATE callback of the IP Connection have a device_identifier parameter to specify the Brick's or Bricklet's type.