Remote Operation

Monitoring the Instrument

The STATus:PRESet command clears all event registers and sets all bits in the event enable registers. Use the *CLS common command to clear all event registers and all queues except the output queue. If *CLS is sent immediately following a program message terminator, the output queue is also cleared. In addition, the request for the *OPC bit is also cleared.

For an example program using the status registers, refer to “Example 9. Monitoring the status registers” on page 4-29.

Status Byte

The Status Byte contains summary bits that monitor activity in the other status registers and queues. The register’s bits are set and cleared by summary bits from other registers or queues. If a bit in the Status Byte goes high, query the value of the source register to determine the cause.

Command

Use

HP-IB serial poll command

Returns the status byte value. Reads bit 6 as the

 

Request Service (RQS) bit and clears the bit

 

which clears the SRQ interrupt.

*STB? common command

Returns the status byte value. Reads bit 6 as the

 

Master Summary Status (MSS) and does not

 

clear the bit or have any effect on the SRQ inter-

 

rupt.

*SRE common command

Sets or reads the event enable register value

 

(mask).

Standard Status Structure

The Standard Status Structure monitors the following instrument status events: operation complete, query error, device dependent error, execution error, and command error. When one of these events occurs, the event sets the corresponding bit in the register.

Command

Use

*ESR? common command

Returns and clears the value of the event regis-

 

ter.

*OPC common command

When all operations have finished, sets bit 0 of

 

the event register. The query returns a 1 when

 

all operations have finished.

*ESE common command

Sets or returns the value of the event enable reg-

 

ister (mask).

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