Keithley 194 Instruction Manual page 130

IEEE-488 PROGRAMMING
Buffer Pointer Values (US-Ull)
These status commands return the buffer pointers pro-
grammed with the B command as indicated below.
Bl,m: Measurement buffer start pointer
B2,m: Measurement buffer end pointer
B3,m: Reading buffer start pointer
To access the desired parameter, simply send the desired
command and address the instrument to talk in the nor-
mal manner. As with all the LJ command options, the car-
responding status will be transmitted only once after each
command is sent. The formats for the buffer pointer status
values are shown in Figure 4.12.
NOTES:
1. The programmed terminator (default, CR LF) will be
transmitted at the end of each status word.
2. EOI will be transmitted at the end of the status word
unless disabled with the K command.
3. The U12 performs the same function as the LIST com-
mand; see paragraph 4.10
HP-85 Programming Example--Enter and run the program
below to obtain and display the status words.
In the example program, the instrument is placed in
remote (line 20), and a loop is set up to request the 12 status
words (line 30). The status word command is then sent
to the instrument (line 40), and status is then requested
and displayed (lines 50 and 60).
Model 8573 Programming Example-Add the following
lines to the modified declaration file to obtain and display
the status words.
In the above program, the instrument is first placed in
remote (line lo), and a loop is set up to obtain the status
words (line 20). The unit is then programmed for status
(lines 30 and 40), and the corresponding status word is
then obtained and displayed (lines 50.70).
4.9.16 SRQ Mode (M) and Status Byte Format
The SRQ command controls which of a number of condi-
tions within the Model 194 will cause the instrument to
assert SRQ (Service Request). Once an SRQ has been
generated, the status byte can be checked to determine if
the Model 194 was the instrument that asserted SRQ and,
if so, what conditions caused it to do so. Note that addi-
tional data and error conditions can be checked by using
the Ul and U2 status commands, as discussed in
paragraph 4.9.15.
Upon power up, or after a DCL or SDC, the unit will be
in the MO (SRQ disabled) mode.
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