HP 1GSa/s Digitizing Oscilloscope 16532A Self-Test Descriptions, Data Memory Test, Timebase Test

HP 16532A - Service

Self-Test Descriptions

The following self-tests check the major components of the HP 16532A oscilloscope module as well as all associated circuitry. When the self-tests have all been completed with a "PASS" status, the major data and control pipelines in the HP 16532A oscilloscope module are functioning properly.

Data Memory Test

This test verifies the correct operation of the FISO (fast-in/slow-out) data memory on each board. Test patterns are written into the memory and then read and compared with known values.

Timebase Test

The pre-trigger and post-trigger delay modes are first tested by programming a predetermined time interval in the trigger counters. At the end of the time intervals, the arm, trigger, and run status bits are read and compared with known values. The coarse and fine interpolators are then checked by reading the values of the interpolator counters after a simulated acquisition. The counter values are then com- pared with a known value. Finally, the sample clock is checked by programming a sample clock frequency and then reading the status of the clock to detect when one clock period has elapsed. The clock period time interval is then compared with a known value.

A/D Test

This test verifies the correct operation of the A/D convertor on each board. A check of the trigger in Trigger Immediate mode is first made. The A/D convertors are then exercised by setting the reference voltage and channel offset such that a simulated acquisition obtains data in the extremes and middle of the quantization range of the A/D convertor. After each simulated acquisition, the data is compared with known values.

D/A Test

This test verifies the correct operation of the D/A convertor on each board. Both the offset and trigger level D/A convertors for each channel are set to a reference level and then changed. The logic trigger IC is programmed to detect the changes. The detection of a correct trigger indicates that the D/A convertor is operating normally.

Trigger Test

This test verifies the correct operation of the trigger components on each board. First, the logic trigger memory is checked by writing and then reading known patterns. The logic qualifiers, logic trigger output, and trigger holdoff are checked.

IMB Test

This test verifies the correct operation of the oscilloscope card interface to the intermodule bus.

All Tests

This will automatically execute each test, one at a time, until all tests are done.

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