Chapter 4 Command Reference

:SYSTem Subsystem

:SYSTem Subsystem

This subsystem collects together the capabilities that are not related to instrument performance.

:SYSTem:COMMunicate Subtree

The :SYSTem:COMMunicate subtree collects together the configuration of the control/communication interfaces.

The :SYSTem:COMMunicate:SERial subtree controls the physical configuration of the RS-232C port. Any command to change the settings takes effect immediately upon receipt of the “program message termination.” These settings are stored in non-volatile memory, and are unaffected by power-on, save/recall, and *RST.

The :SYSTem:COMMunicate:SERial:TRANsmit subtree controls parameters associated with transmission.

The Counter will always use one start bit and one stop bit.

:SYSTem:COMMunicate:SERial:CONTrol:DTR IBFull ON LIMit

Sets or queries the hardware pacing scheme.

The ON parameter (which is equivalent to DTR: HIGH in the front-panel Utility menu) indicates that the DTR (Data Terminal Ready) line, which is pin 4 of the RS-232 connector , is always asserted

(HIGH) to always be ready to allow data to be sent to the printer. Choose the ON parameter when the printer or cable you are using does not support handshaking.

The IBFull parameter (which is equivalent to DTR: HW PACE in the front-panel Utility menu) sets the RS-232 DTR line to indicate when the device is ready to receive. When the number of received bytes in the input buffer of the Counter reaches a stop thresholdrhhhe the Counter will de-assert the DTR line. When the number of bytes has been reduced to a start threshold, the Counter will assert DTR, indicating that it can receive input again. The Counter will also monitor the state of the DSR (Data Set Ready) line, which is pin 6 of the RS-232 connector, and will stop transmission if either of those lines becomes de-asserted. Choose the IBFull parameter when the printer and cable you are using require handshaking for counter-to-printer communication.

The LIMit parameter (which is equivalent to DTR: LIMIT in the front-panel Utility menu) indicates that the RS-232 DTR line will be used to indicate out of limit. The LIMit parameter will force the DTR line HIGH if the measurement is in limit, and LOW if the measurement is out of limit.

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Programming Guide