Modbus - RS232 Bricklet¶

Basic Functions¶

BrickletRS232.write¶

Function ID:	1
Request:	message -- char[60] length -- uint8
Response:	written -- uint8

Writes a string of up to 60 characters to the RS232 interface. The string can be binary data, ASCII or similar is not necessary.

The length of the string has to be given as an additional parameter.

The return value is the number of bytes that could be written.

See set_configuration for configuration possibilities regarding baudrate, parity and so on.

BrickletRS232.read¶

Function ID:	2
Request:	empty payload
Response:	message -- char[60] length -- uint8

Returns the currently buffered message. The maximum length of message is 60. If the length is given as 0, there was no new data available.

Instead of polling with this function, you can also use callbacks. See enable_read_callback and CALLBACK_READ callback.

BrickletRS232.set_configuration¶

Function ID:	6
Request:	baudrate -- uint8 parity -- uint8 stopbits -- uint8 wordlength -- uint8 hardware_flowcontrol -- uint8 software_flowcontrol -- uint8
Response:	no response

Sets the configuration for the RS232 communication. Available options:

• Baudrate between 300 and 230400 baud.
• Parity of none, odd, even or forced parity.
• Stopbits can be 1 or 2.
• Word length of 5 to 8.
• Hard-/Software flow control can either be on or off but not both simultaneously on.

The default is: 115200 baud, parity none, 1 stop bit, word length 8, hard-/software flow control off.

The following meanings are defined for the parameters of this function:

• 0: 300, for baudrate
• 1: 600, for baudrate
• 2: 1200, for baudrate
• 3: 2400, for baudrate
• 4: 4800, for baudrate
• 5: 9600, for baudrate
• 6: 14400, for baudrate
• 7: 19200, for baudrate
• 8: 28800, for baudrate
• 9: 38400, for baudrate
• 10: 57600, for baudrate
• 11: 115200, for baudrate
• 12: 230400, for baudrate
• 0: none, for parity
• 1: odd, for parity
• 2: even, for parity
• 3: forced parity 1, for parity
• 4: forced parity 0, for parity
• 1: 1, for stopbits
• 2: 2, for stopbits
• 5: 5, for wordlength
• 6: 6, for wordlength
• 7: 7, for wordlength
• 8: 8, for wordlength
• 0: off, for hardware_flowcontrol
• 1: on, for hardware_flowcontrol
• 0: off, for software_flowcontrol
• 1: on, for software_flowcontrol

BrickletRS232.get_configuration¶

Function ID:	7
Request:	empty payload
Response:	baudrate -- uint8 parity -- uint8 stopbits -- uint8 wordlength -- uint8 hardware_flowcontrol -- uint8 software_flowcontrol -- uint8

Returns the configuration as set by set_configuration.

The following meanings are defined for the parameters of this function:

• 0: 300, for baudrate
• 1: 600, for baudrate
• 2: 1200, for baudrate
• 3: 2400, for baudrate
• 4: 4800, for baudrate
• 5: 9600, for baudrate
• 6: 14400, for baudrate
• 7: 19200, for baudrate
• 8: 28800, for baudrate
• 9: 38400, for baudrate
• 10: 57600, for baudrate
• 11: 115200, for baudrate
• 12: 230400, for baudrate
• 0: none, for parity
• 1: odd, for parity
• 2: even, for parity
• 3: forced parity 1, for parity
• 4: forced parity 0, for parity
• 1: 1, for stopbits
• 2: 2, for stopbits
• 5: 5, for wordlength
• 6: 6, for wordlength
• 7: 7, for wordlength
• 8: 8, for wordlength
• 0: off, for hardware_flowcontrol
• 1: on, for hardware_flowcontrol
• 0: off, for software_flowcontrol
• 1: on, for software_flowcontrol

BrickletRS232.set_break_condition¶

Function ID:	10
Request:	break_time -- uint16
Response:	no response

Sets a break condition (the TX output is forced to a logic 0 state). The parameter sets the hold-time of the break condition (in ms).

New in version 2.0.2 (Plugin).

Advanced Functions¶

BrickletRS232.get_identity¶

Function ID:	255
Request:	empty payload
Response:	uid -- char[8] connected_uid -- char[8] position -- char hardware_version -- uint8[3] firmware_version -- uint8[3] device_identifier -- uint16

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. 

Callback Configuration Functions¶

BrickletRS232.enable_read_callback¶

Function ID:	3
Request:	empty payload
Response:	no response

Enables the CALLBACK_READ callback.

By default the callback is disabled.

BrickletRS232.disable_read_callback¶

Function ID:	4
Request:	empty payload
Response:	no response

Disables the CALLBACK_READ callback.

By default the callback is disabled.

BrickletRS232.is_read_callback_enabled¶

Function ID:	5
Request:	empty payload
Response:	enabled -- bool

Returns true if the CALLBACK_READ callback is enabled, false otherwise.

Callbacks¶

BrickletRS232.CALLBACK_READ¶

Function ID:	8
Response:	message -- char[60] length -- uint8

This callback is called if new data is available. The message has a maximum size of 60 characters. The actual length of the message is given in addition.

To enable this callback, use enable_read_callback.

BrickletRS232.CALLBACK_ERROR¶

Function ID:	9
Response:	error -- uint8

This callback is called if an error occurs. Possible errors are overrun, parity or framing error.

New in version 2.0.1 (Plugin).

The following meanings are defined for the parameters of this function:

• 1: overrun, for error
• 2: parity, for error
• 4: framing, for error