HP VXI E1432A manual Possible Trigger Line Conflict

HP E1432A User's Guide

Using the HP E1432A

All modules except the “system module” need to be set to use the VXI TTL trigger lines as the clock source. Use hpe1432_setClockSource for this.

Set the “system module” to output the clock. Use hpe1432_setClockMaster for this. After this is done, all system sync pulses come from the “system module” and drive the measurement state machines on all boards in the group.

Possible Trigger Line Conflict

The following describes a scenario where HP E1432A modules might conflict and prevent a proper measurement. The conditions allowing the conflict are complex but must be understood by the user.

After a measurement has completed, the modules are left set up. If a module (call it module ‘A’) is driving the TTL trigger lines and a different group is started which also drives the TTL trigger lines (and that different group does not include module ‘A’), then module ‘A’ will conflict and prevent the other group from functioning. In this case make a call to hpe1432_finishMeasure (using the old group ID which includes ‘A’) to turn off module ‘A’ and allow the new group to function.

Note that if the new group includes all modules of the old group, the conflict will not occur since hpe1432_initMeasure will reset all modules as needed. Also note that single-module groups do not drive the TTL trigger lines, so single-module groups are immune from causing or receiving this conflict.

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