/ 
Lab-Measurement-3.810
River stage zero No dependents
/ Lab::Bus::LinuxGPIB

NAME

Lab::Bus::LinuxGPIB - LinuxGPIB bus

VERSION

version 3.810

SYNOPSIS

This is the GPIB bus class for the GPIB library linux-gpib (aka libgpib0 in the debian world).

my $GPIB = new Lab::Bus::LinuxGPIB({ gpib_board => 0 });

or implicit through instrument and connection creation:

my $instrument = new Lab::Instrument::HP34401A({
  connection_type => 'LinuxGPIB',
  gpib_board => 0,
  gpib_address=>14,
}

DESCRIPTION

See http://linux-gpib.sourceforge.net/ for details on the LinuxGPIB package. The package provides both kernel drivers and Perl bindings. Obviously, this will work for Linux systems only. On Windows, please use Lab::Bus::VISA. The interfaces are (errr, will be) identical.

Note: you don't need to explicitly handle bus objects. The Instruments will create them themselves, and existing bus will be automagically reused.

In GPIB, instantiating two bus with identical parameter "gpib_board" will logically lead to the reuse of the first one. To override this, use the parameter "ignore_twins" at your own risk.

CONSTRUCTOR

new

my $bus = Lab::Bus::GPIB({
   gpib_board => $board_num
 });

Return blessed $self, with @_ accessible through $self->config().

gpib_board: Index of board to use. Can be omitted, 0 is the default.

Thrown Exceptions

Lab::Bus::GPIB throws

Lab::Exception::GPIBError
  fields:
  'ibsta', the raw ibsta status byte received from linux-gpib
  'ibsta_hash', the ibsta bit values in a named hash ( 'DCAS' => $val, 'DTAS' => $val, ... ). 
                Use Lab::Bus::GPIB::VerboseIbstatus() to get a nice string representation

Lab::Exception::GPIBTimeout
  fields:
  'Data', this is meant to contain the data that (maybe) has been read/obtained/generated despite and up to the timeout.
  ... and all the fields of Lab::Exception::GPIBError

METHODS

connection_new

$GPIB->connection_new({ gpib_address => $paddr });

Creates a new connection ("instrument handle") for this bus. The argument is a hash, whose contents depend on the bus type. For GPIB at least 'gpib_address' is needed.

The handle is usually stored in an instrument object and given to connection_read, connection_write etc. to identify and handle the calling instrument:

$InstrumentHandle = $GPIB->connection_new({ gpib_address => 13 });
$result = $GPIB->connection_read($self->InstrumentHandle(), { options });

See Lab::Instrument::Read().

TODO: this is probably not correct anymore

connection_write

$GPIB->connection_write( $InstrumentHandle, { Cmd => $Command } );

Sends $Command to the instrument specified by the handle.

connection_read

$GPIB->connection_read( $InstrumentHandle, { Cmd => $Command, ReadLength => $readlength, Brutal => 0/1 } );

Sends $Command to the instrument specified by the handle. Reads back a maximum of $readlength bytes. If a timeout or an error occurs, Lab::Exception::GPIBError or Lab::Exception::GPIBTimeout are thrown, respectively. The Timeout object carries the data received up to the timeout event, accessible through $Exception->Data().

Setting Brutal to a true value will result in timeouts being ignored, and the gathered data returned without error.

timeout

$GPIB->timeout( $connection_handle, $timeout );

Sets the timeout in seconds for GPIB operations on the device/connection specified by $connection_handle.

config

Provides unified access to the fields in initial @_ to all the child classes. E.g.

$GPIB_Address=$instrument->config(gpib_address);

Without arguments, returns a reference to the complete $self->config aka @_ of the constructor.

$config = $bus->config();
$GPIB_PAddress = $bus->config()->{'gpib_address'};

CAVEATS/BUGS

Few. Also, not a lot to be done here.

SEE ALSO

COPYRIGHT AND LICENSE

This software is copyright (c) 2022 by the Lab::Measurement team; in detail:

Copyright 2011       Andreas K. Huettel, Florian Olbrich
          2012       Florian Olbrich, Hermann Kraus, Stefan Geissler
          2016       Charles Lane, Simon Reinhardt
          2017       Andreas K. Huettel
          2020       Andreas K. Huettel

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.