Status Byte and Event Registers |
The instrument includes a number of standard registers:
the "Standard Event Status Register", "Standard Event Status Enable Register",
"Status Byte Register", "Service Request Enable Register",
"Event Status Register 0", and "Event Status Enable Register 0".
For GP-IB, each bit is masked by setting the Standard Event Status Enable Register (initialized to zero at power on).
For RS-232C and LAN interfaces, only the values of the status byte, Standard Event Status Register, and Event Status Register 0 are valid.
The enable registers have no effect and are disregarded.
Each bit of the status byte is a summary (logical OR) of the event register corresponding to that bit.
Status byte |
Contents |
bit 7 |
Unused: 0 |
bit 6 |
Set when a service request is issued. |
bit 5 |
Event summary bit. |
bit 4 |
Message available |
bit 3 |
Unused: 0 |
bit 2 |
Unused: 0 |
bit 1 |
Unused: 0 |
bit 0 |
Event summary bit 0 |
Each bit (event) is masked by writing the Service Request Enable Register (initialized to zero at power on).
The following commands read the status byte and write and read the Service Request Enable Register.
Read the status byte |
*STB? |
Write the Service Request Enable Register |
*SRE |
Read the Service Request Enable Register |
*SRE? |
Bit 5 of the status byte indicates the summary of this register.
For GP-IB, each bit is masked by writing the Standard Event Status Enable Register (initialized to zero at power on).
The following events clear the contents of the Standard Event Status Register:
When the *CLS command is received.
When the contents have been read by an *ESR? query.
When power is turned off and on again.
Standard Event |
Contents |
bit 7 |
Power has been turned on again. |
bit 6 |
User request: not used. |
bit 5 |
Command error. |
bit 4 |
Execution error. |
bit 3 |
Device-dependent error. |
bit 2 |
Query error. |
bit 1 |
Request for controller rights (not used) Unused: 0 |
bit 0 |
Operation finished. |
Each event is masked by writing the Standard Event Status Enable Register (initialized to zero at power on).
The following commands are used to read the Standard Event Status Register, and to write and read the Standard Event Status Enable Register.
Read the Standard Event Status Register |
*ESR? |
Write the Standard Event Status Enable Register |
*ESE |
Read the Standard Event Status Enable Register |
*ESE? |
The summary of this register is set in bit 0 of the status byte.
For GP-IB, each bit is masked when the Event Status Enable Register 0 (which starts off at zero when the power is turned on) is set.
The following events clear the contents of Event Status Register 0:
When the *CLS command is received.
When the contents have been read by an :ESR0? query.
When power is turned off and on again.
Event Status Register 0 |
Contents |
bit 7 |
FAIL (NG) waveform decision occurred. |
bit 6 |
FAIL (NG) parameter decision occurred. |
bit 5 |
Parameter calculation finished. |
bit 4 |
Waveform processing calculation finished. |
bit 3 |
Printer operation finished (print, or copy output). |
bit 2 |
Trigger wait finished (set when a trigger event occurs). |
bit 1 |
Measurement operation concluded (set by STOP). |
bit 0 |
Error not related to the GP-IB interface. |
The following commands read the Event Status Register 0,
and write and read the Event Status Enable Register 0.
Read Event Status Register 0 |
:ESR0? |
Write Event Status Enable Register 0 |
:ESE0 |
Read Event Status Enable Register 0 |
:ESE0? |