User`s manual

Agilent E8462A Relay Multiplexer Command Reference 101

STATus

The STATus subsystem reports the bit values of the Operation Status Register. It

also allows you to unmask the bits you want reported from the Standard Event

Subsystem Syntax STATus

:OPERation

:CONDition?

:ENABle <number>

:ENABle?

[:EVENt?]

:PRESet

The STATus system contains four registers, two of which are under IEEE 488.2

control; the Standard Event Status Register (*ESE?) and the Status Byte Register

(*STB?). The operational status bit (OPR), service request bit (RQS), standard event

summary bit (ESB), message available bit (MAV) and questionable data bit (QUE)

in the Status Byte Register (bits 7, 6, 5, 4 and 3 respectively) can be queried with the

*STB? command. Use the *ESE? command to query the "unmask" value for the

Standard Event Status Register (the bits you want logically OR'd into the summary

bit). The registers are queried using decimal weighted bit values. The decimal

equivalents for bits 0 through 15 are included in figure 3-1.

A numeric value of 256 executed in a

STAT:OPER:ENABle <number> command

allows only bit 8 to generate a summary bit. The decimal value for bit 8 is 256.

The decimal values are also used in the inverse manner to determine which bits are

set from the total value returned by an

EVENt or CONDition query. The "SWITCH"

driver exploits only bit 8 of Operation Status Register. This bit is called the scan

complete bit which is set whenever a scan operation completes. Since completion of

a scan operation is an event in time, you will find that bit 8 will never appear set when

STAT:OPER:COND? is queried. However, you can find bit 8 set with the

STAT:OPER:EVEN? query command.