Keithley 6512 Instruction Manual page 74

Trigger Overrun—Set when a trigger is received when the instrument is still processing a reading from a pre-
vious trigger.
Number Error—Set when an out-of-range calibration value is received.
Data
In a similar manner, the U2X sequence allows access to instrument data conditions. When this command is
Conditions transmitted, the instrument will transmit the data condition word shown in Figure 3-5 the next time it is ad-
dressed to talk. This information will be transmitted only once each time the command is received. As with
the U1 error word, the U2 word is made up of ASCII characters representing binary values. Unlike the U1
error word, however, the U2 data condition word will not be cleared when read; thus, instrument status in the
U2 word is always current.
Figure 3-5
U2 status (data condition) format
The various bits in the data condition word include:
Data Store Full—Set when all 100 readings have been stored in the data store memory. Cleared by requesting
a data store reading over the bus.
Z and N—Represents the same information as the corresponding zero correct (Z) and suppress (N) bytes in
the U0 status word.
Temporary Calibration—Set when new calibration parameters not yet stored in NVRAM have been received,
or if power-up recall of NVRAM data was in error. Cleared when NVRAM storage is performed.
Programming See Appendix D for an example program that can be used to request the status, error, and data
Note
conditions words from the instrument.
Examples
U0X
U1X
6512 0/1 0 0/1
MODEL
NUMBER
PREFIX
1 = DATA
STORE FULL
Z (ZERO CORRECT)
0 = OFF
1 = ON
N (SUPPRESS)
0 = OFF
1 = ON
1 = TEMPORARY CALIBRATION
Request status word.
Request error word.
0/1 0/1 0000 <CR LF>
ALWAYS
ZEROES
TERMINATOR
(DEFAULT
VALUES
SHOWN)
IEEE-488 Programming
3-19