Keithley 2100 User Manual page 134

Appendix B: Remote Interface Reference
Figure B-2
Questionable Data
About the Status byte
The conditions from other status registers will be reported by the status byte summary register.
The query data, waiting in the multimeter's output buffer, is reported immediatedly through the
"message available" in bit 4. Besides, bits are not latched in the summary registers. In addition, to
clear an event register will clear the according bits in the status byte summary register. And to read
all messages in the output buffer, including all pending queries, will clear the message available
bit.
The following table shows the definition of each bit (see
Table B-1
Definition of each bit
Bit
0. Not used
1. Not used
2. Not used
3. Questionable Data
4. Message available
5. Standard event
6. Request service
7. Not used
B-22
Model 2100 6 1/2-Digit Resolution Digital Multimeter User's Manual
Decimal
Value
1
2
4
8 One or more bits are set in the questionable data register (bits
have to be "enabled" in the enable register.
16 Data in the DMM's output buffer is available.
32 One or more bits are set in the Standard Event Register (bits
have to be "enabled" in the enable register.
64 The DMM is requiring service (serial poll).
128
Section Topics
Return to
Table B-1).
Definition
Set to 0.
Set to 0.
Set to 0.
Set to 0.
2100-900-01 Rev. D / September 2011