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HP E1433A User's Guide
The Tachometer Option
LED’s and Connectors for the Tachometer Option.
Status LEDs
Fail: This is the standard VXI “Failed” indicator. It lights briefly when powering up and normally goes out after a few seconds. If it stays on it indicates a hardware failure in the module.
Acs: This is the standard VXI “Access” indicator. When it is on, it indicates that another device on the bus is contacting the module, for example to transfer data or read registers.
Trigger: This LED flashes on each time an edge is detected on the tachometer signal, so when it is blinking it indicates that the tachometer signal is on. (For an HP E1433A that does not have the Tachometer option, this LED is defined differently.)
SMB Connectors
Tach1: This is one of the two tachometer inputs. Tach1 cannot be configured as an external trigger.
Tach2: This is the second of the two tachometer inputs. Tach2 can also be configured (via software) to be an external trigger input
ExTrig: This allows for an external trigger input to the HP E1433A. The input signal must be TTL, other characteristics can be defined in software. ExTrig can be enabled or disabled in software.
Input Connectors (1 or 2)
These connectors are attached to the cables from an