•The output queue

•The Service Request Enable Register

•The Standard Event Status Enable Register

•The power-on flag

•Calibration data

•Protected user data

*SRE <mask>

Service Request Enable. When a service request event occurs, it sets a corresponding bit in the Status Byte Register (this happens whether or not the event has been enabled (unmasked) by *SRE). The *SRE command allows you to identify which of these events will assert a service request (SRQ). When an event is enabled by *SRE and that event occurs, it sets a bit in the Status Byte Register and issues an SRQ to the computer. You enable an event by specifying its decimal weight for <mask>. To enable more than one event, specify the sum of the decimal weights.

Example *SRE 160

Enables bits 5 & 7. Respective weights

 

are 32 + 128 = 160.

*SRE?

Status Register Enable Query. Returns the weighted sum of all enabled (unmasked) events (those enabled to assert SRQ) in the Status Byte Register.

Example *SRE?

Sends Status Register Enable query.

*STB?

Status Byte Register Query. Returns the weighted sum of all set bits in the Status

Byte Register.

Comments You can read the Status Byte Register using either the *STB? command or by doing a SICL ireadstb function call. There are some subtle differences between *STB? and ireadstb. You can use either method to read the state of bits 0-5 and bit 7. Bit 6 is treated differently depending on whether you use *STB? or ireadstb. In general, use ireadstb inside interrupt service routines, not *STB?.

Example *STB?

Sends Status Byte Register query.

*TST?

Self-Test.Causes an instrument to execute an internal self-test and returns a response showing the results of the self-test. A zero response indicates that self-test passed. A value other than zero indicates a self-test failure or error.

Example *TST?

Execute self-test, return response.

32 Command Reference

Chapter 3