Agilent Technologies 6031A, 6035A Sre?, Bit Configuration of Status Byte Register, Oper, Stb?

*SRE

Meaning and Type

Service Request Enable Device Interface

Description

This command sets the condition of the Service Request Enable Register. This register determines which events of the Status Byte Register (see *STB for its bit configuration) are summed into the MSS (Master Status Summary) and RQS (Request for Service) bits. RQS is the service request bit that is cleared by a serial poll; the MSS is not cleared when read.

A 1 in any Service Request Enable Register bit position enables the corresponding Status Byte bit to set the RQS and MSS bits. All the enabled Service Request Enable Register bits then are logically ORed to cause Bit 6 of the Status Byte Register to be set. See "Status Reporting" for more details concerning this process.

If *PSC is programmed to zero, *SRE causes a write cycle to nonvolatile memory. Non volatile memory has a finite maximum number of write cycles. Programs that repeatedly cause write cycles to nonvolatile memory can eventually exceed the maximum number of write cycles and cause the memory to fail.

Command Syntax	*SRE <NRf>
Parameters	0 to 255
Default Value	(See *PSC)
Example	*SRE 20
Query Syntax	*SRE?
Returned Parameters	<NR1> (Register binary value)

*STB?

Meaning and Type

Status Byte Device Status

Description

This query reads the Status Byte register without clearing it. The register is cleared only when subsequent action clears all its set bits. See "Status Reporting" for more information about the Status Byte register.

A serial poll also returns the value of the Status Byte register, except that bit 6 returns RQS instead of MSS. A serial poll clears RQS, but not MSS. When MSS is set, it indicates that the power supply has one or more reasons for requesting service.

Bit Configuration of Status Byte Register

Bit Position

Condition

Bit Weight

7

OPER

128

6

1MSS

64

5

ESB

32

4

MAV

16

3

QUES

8

2

4

1

2

2

0

1

ESB = Event status byte summary; MAV = Message available; MSS = Master status summary; OPER = Operation status summary; QUES = Questionable status summary

lAIso represents RQS (Request for service). 2These bits are always zero.

Query Syntax	*STB?
Returned Parameters	<NR1> (Register binary value)

94Standard Commands for Programmable Instruments (SCPI)