Keithley KPCI-3110, User Manual

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C-26 Systematic Problem Isolation KPCI-3110 and KPCI-3116 User’s Manual
General-purpose digital I/O software test
This test checks whether your application software is performing general-purpose digital I/O
functions properly.
Test summary
The following summarizes the test procedure:
• Wire an STP-3110 screw terminal accessory in a loop-back configuration. Connect the chan-
nel 0 general-purpose digital I/O terminals, bit-for-bit, to the channel 3 general-purpose dig-
ital I/O terminals. Connect the channel 1 terminals, bit-for-bit, to the channel 2 terminals.
(These are the same loop-back connections as made for the general-purpose digital I/O
hard-
ware test.)
•
Using your application software, set the channel 0 and 1 outputs in a particular alternating
OFF-ON bit pattern and check channels 2 and 3 inputs for the same bit pattern. Repeat, using
a second ON-OFF bit pattern.
Your application software is performing general-purpose digital I/O satisfactorily if all bits
respond appropriately.
Equipment for general-purpose digital I/O software test
All I/O is set and read using your application software; no instruments are required. However,
you must wire an STP-3110 screw terminal accessory to J2 in the loop-back configuration. If
possible, use a screw terminal accessory that is reserved for I/O tests. Avoid using a screw termi-
nal accessory that is normally connected to your external circuits. You thereby avoid the extra
labor and potential wiring errors involved in disconnecting and later reconnecting your external
circuits.
Procedure for general-purpose digital I/O software test
NOTE
The bit patterns prescribed in this procedure are shown graphically as
follows:
•
OFF bits appear as white squares
•
ON bits appear as green squares when the manual is viewed in color
or as light gray squares when the manual is viewed in black and
white.
Perform the I/O hardware test as follows:
1. Turn off the host computer
2. If a screw terminal accessory is attached to the J2 connector of the KPCI-3110 or KPCI-3116
I/O board, remove it. No circuits should be connected to Analog I/O connections during
these tests.
3. Attach the wired screw terminal accessory.
4. Turn on the host computer and boot Windows 95, 98, or NT.
5. Start DriverLINX and your application software.
6. Set up your application software to configure and monitor general-purpose digital I/O bits.