Stanford Research Systems SR620, Manual

Page: 56 / 124

40 Programming Commands
SR620 Universal Time Interval Counter
$PHK(?) j
The $PHK command is used to exercise the
printer port handshaking lines. The value of j (0 or
1) sets the state of the -init and -strobe lines. The
query $PHK? reads the value of the busy line.
$POT? j
The $POT? query reads the dc voltage of the front
panel potentiometers (NOT the trigger level) in
units of 10mV.
*CAL?
The *CAL? common query runs the autocal
procedure. This query will return the following
status value:
value meaning
0 no
error
1 SR620 not warmed up, can't cal.
2 no trigger error
3 can't find edge on start tac
4 can't find edge on start fine seek
5 start tac calbyte out of range
6 start tac non-convergence
7 start linearity byte out of range
19-23 stop tac errors same as start value n - 16
*TST?
The *TST? common query runs the selt test
procedure. The query will return the following
status value:
value meaning
0 no
error
4 cpu error
5 system ram error
6 video ram error
16 count gate error
17 chan 2 count
≠
0
18 chan 1 count error
19 chan 1 count
≠
0
20 chan 2 count error
32 frequency gate error
33 excessive jitter
34 frequency insertion delay error
35 time interval insertion delay error
Errors 33-35 can usually be eliminated by running
the autocal procedure. The other errors are
usually caused by hardware problems.
BYTE (?) j{,k}
The BYTE command set the value of linearization
byte j to k. Parameter j may have a value from 0
to 129, and k may range from 0 to 255. NOTE:
this command will alter the calibration of the
SR620. However, running autocal will correct the
problem.
WORD (?) j{,k}
The WORD command sets the value of calibration
word j to k. Parameter j may have a value from 0
to 51, while k may range from 0 to 65535. NOTE:
this command will alter the calibration of the the
SR620. To correct the calibration the factory
calibration bytes may be recalled (see the
Calibration section).
STATUS BYTE DEFINITIONS
Status Reporting
The SR620 reports on its status by means of four
status bytes: the serial poll byte, the standard
status byte, the TIC status byte, and the error
status byte.
On power on the SR620 may either clear all of its
status enable registers or maintain them in the
state they were in on power down. The action
taken is set by the *PSC command and allows
things such as SRQ on power up .
Serial Poll Status Byte:
bit name usage
0
ready No measurements are in
progress
1 print ready No prints are in progress
2 Error An unmasked bit in the error
status register has been
set.
3 TIC An unmasked bit in the TIC
status register has been set.
4 MAV The gpib output queue is
non-empty
5 ESB An unmasked bit in the
standard status byte has
been set.
6 RQS/MSS SRQ (Service Request)bit.
7 scan ready no scans are in progress
The Error, TIC, ESB bit are set whenever any
unmasked bit (bit with the corresponding bit in the