hp54500_get_waveform (ul_scopes)

	status.i4.v = hp54500_get_waveform(data.r4a.r,chan.i4.v,
				dev_address.i4.v,points.i4.r, mode.i4.v)

	Get trace data for a channel of an HP 54500 two or four channel
	scope.  The returned data is an (x,y) scaled pair.  The number of
	points in the trace is also returned but there will be 2*points 
	for the number of values returned in data.

       data		returned trace data.  The data is returned as x,y 
			coordinates.  There will be 2*number_pts for 
			allocating memory.
       chan		channel to request data for: 
			HP_CHAN1 -> Channel 1
			HP_CHAN2 -> Channel 2
			HP_CHAN3 -> Channel 3
			HP_CHAN4 -> Channel 4

	dev_address	address of scope; A previos call to gpib_select()
			will have to be made to establish communication 
			to correct VME.
	points		returns the number of points the scope is using
	mode		Mode is the area which the data is transfered
			from:(if WMEM chan is still the WMEM channel)
			WMEM -> Traces are returned from waveform memory
			CHANNEL -> Traces data of channel is returned.


	This function returns ACNET status values as follows:

	CBS_OK			success
	CBS_INVARG		invalid device address
	otherwise		GAS error

	This function requires the following include files:

	ul_scopes_h:hpdefs_h

	Related functions:

	hp54500_change_dir, hp54500_display_wmem, hp54500_format_disk, 
	hp54500_get_disk_dir, hp54500_get_waveform, hp54500_init, 
	hp54500_load_from_disk, hp54500_message, hp54500_num_points,
	hp54500_set_acquire, hp54500_set_channel, hp54500_set_display,
	hp54500_set_root, hp54500_set_timebase, hp54500_set_trigger,
	hp54500_set_utilities, hp54500_set_waveform, hp54500_store_wmem,
	hp54500_write_to_disk, hp54500_num_screens, hp54500_del_disk_file.