Envision Peripherals NV3128 manual Signal Path, Mapping And Command Problems

SIGNAL PATH

The quickest way to isolate problems in a single connection is by module substitution. If sufficient spares are not available to carry out this strategy, the next best recourse is path substitution:

1.Route the problem signal to a new crosspoint/output address.

2.If new route does not correct the problem, the source port circuitry is probably faulty. Verify by reconnecting the source machine to a new port, or by swapping the two I/O modules. The upper of the two I/O modules supports ports 1-64. The lower module supports ports 65-128. Do not overlook the possibility of a problem in the external cabling or equipment.

3.Assuming the new route of Step 1 passed signal, route any signal to the problematic output with the I/O cards swapped. Signal passes? Then the I/O module is defective. No Go? The crosspoint module is at fault.

MAPPING AND COMMAND PROBLEMS

Most switch problems result from the complexity of the control system interface. Refer to section 3 (older systems) or the UniDiag manual (newer systems) for a discussion of the PC-based diagnostic and control utilities furnished with the routing switch.

NV3128 RS-422A Machine Control Data Routing Switch 5-5