1902 function library for Labview 6.1 - Tim Pragnell, University of Oxford
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This is based on the library provided by Patrick Haggard of UCL. I have
expanded the whole thing for my own purposes and addressed a number of
problems with the basic driver software:

1. Reads and writes are optimised to be much faster - they do not wait a
fixed time, but return as soon as a command has produced a result.
2. There was a problem with resetting or initialising the 1902 when
driven by labview serial port drivers. It could become unaddressable
after a non-existant channel was addressed or if it happened to power up
in that state. This has been solved by providing a library routine '1902
Kick'.
3. All relevant library routines can address combinations of 1902
channels. We use dual 1902s with half of them labelled channels 0 and 1
and half labelled 2 and 3. The software will enable 2&3 modules to be
addressed as if they were 0&1 modules, or to be addressed as channels 0
to 3 when two dual modules are connected together with a dual rs232
lead.
4. A number of higher-level library routines have been provided e.g.
'set closest gain'.


1902set.ctl is a front panel control which can be used for setting basic
1902 parameters.

1902.llb is a labview 6.1 library. The higher level Vis in it are:


1902Kick.vi			Initialises serial port and looks for
				amplifier channels. Reports back if
				1902 not found.

1902SetInputParameters.vi	Sets up input source, coupling, and
				filtering using 1902set.ctl.

1902SetClosestGain.vi		Sets the closest gain to the one
				requested and outputs the actual gain
				value.

1902SetClosestOffset.vi		Sets the closest offset to the one
				requested and outputs the actual
				offset value.

1902IncrOrDecGain.vi		Set the gain to the next allowed value.

1902IncrOrDecOffset.vi		Set the offset to the next allowed value.

GainToYRange.vi			A simple VI to set the vertical axis of
				graphs given the 1902 gain and the
				DAQ card input range.


Other Vis are subroutines of the above, or can be used on their own or
in combination.
1902ctl.vi is an all-purpose standalone VI for controlling the 1902.
1902SetChannel sets the current channel and does that clever bit where
dual amplifiers labelled channels 2 and 3 can be addressed as if they
were channels 0 and 1 (unless requested not to).