                7912HB example program readme document

This document is meant to describe the functions that are included with 
the 7912HB example program "7912EXPL".  The program is intended to allow 
the user to acquire and measure data immediately by using the ".EXE" file.  

Any mention of the 7912HB also applies equally to the 7912AD.

A ASCII Quickbasic 4.5 listing is included so the user can modify and 
enhance for individual needs.  It is assumed that the user has a National 
Instruments PC2/PC2A card with the appropriate GPIB drivers installed into 
quickbasic. 

If you do not have the National Instruments GPIB card, this program
listing should be a good start for commands to send, etc....

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Here is the main menu and a description of each choice:

*** 7912HB MAIN MENU ***

 1. Store/Recall 7912HB/Vert & Timebase pluggin settings
 2. Serial Poll
 3. Initialize 7912 (defect removal)
 4. Enable/Disable ground reference
 5. Acquire ATC waveform to memory
 6. Acquire averaged waveform to memory
 7. Graph waveform from memory with cursor measurements
 8. DOS Shell
 9. View/Edit program defaults
10. Exit program
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Choice #1 
Store/Recall 7912HB/Vert & Timebase pluggin settings

This selection allows the user to save & recall the settings for the 
mainframe, vertical pluggin, & timebase pluggin.  

This function does not check to see if there are manual pluggins installed.
If there are manual pluggins, an error will occur.  The source program will 
need to be modified for manual pluggins.

The path & filename can be changed using choice #9 (View/Edit program 
defaults).  The default path is C:\ and the default filename is 
"7912SET.".  When this function is invoked, the user enters a file number.  
This number it attached to the tail of the filename (e.g., 7912SET.1)
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Choice #2
Serial Poll

This function performs a serial poll on the main frame, vertical pluggin, 
and timebase pluggin.  The status bytes are displayed on the monitor.

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Choice #3
Initialize 7912 (defect removal)

Selection 3 takes advantage of the builtin function of the 7912HB.  There 
is a possibility of some of the diodes used to convert the signal to be 
defective.  They appear as spikes when data is converted.  Defect removal 
detects where the defects are and removes them when a waveform is acquired.

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Choice #4
Enable/Disable ground reference

Selection 4 grounds the programmable pluggin and acquires the ground trace.  
All subsequent acquisitions will be reference to ground.  This function 
allows the user to turn off the ground reference or redefine at any time.  

An error will occur if a manual vertical pluggin is used.  The source 
code will need to be modified of use with a manual pluggin.

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Choice #5 
Acquire ATC waveform to memory

Acquires an Averaged To Center trace (ATC) waveform.  See the 7912HB 
manual for more details about ATC.  The volts per point & time per point 
are also acquired.  The waveform can be viewed by using choice #7 (Graph 
waveform from memory with cursor measurements).

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Choice #6 
Acquire averaged waveform to memory

Acquires an averaged waveform.  The user selects the number of averages 
from 1 to 64 in powers of 2 (i.e. 1, 2, 4, 8, 16, 32, 64).  See the 
7912HB manual for more details about averaging.  The volts per point & 
time per point are also acquired.  The waveform can be viewed by using 
choice #7 (Graph waveform from memory with cursor measurements).

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Choice #7 
Graph waveform from memory with cursor measurements

Selection 7 displays the acquired waveform from choices 5 or 6.  A screen 
describing user options are displayed and the user is prompted to press 
the space bar to graph the waveform.  

There are cursors that display absolute & delta voltage/time.  The user 
can zoom in on a portion of the waveform.

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Choice #8 
DOS Shell

Allows access to DOS.  The user types 'EXIT' to leave DOS and return 
to the program.

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Choice #9 
View/Edit program defaults

Selection 9 allows changing the primary & secondary address the program 
uses to communicate with the 7912HB.  The storage path & settings filename 
can be modified to suit the users needs.  These defaults are not saved so 
they must be changed whenever the program is executed.

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Choice #10
Exit program

This is the preferred method of exiting the program.

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