PPCH-G™ OPERATION AND MAINTENANCE MANUAL
© 2007 DH Instruments, a Fluke Company
Page 90
received order after the entire message stream has been received, so care in
determining order of execution is needed.
If you are using the RS232 port COM1, the Command type will always generate
a reply so you
must
wait for a reply before issuing another program message.
Because of this, you can only send one Command program message at a time
while using the COM1 port.
Examples:
•
IEEE-488 enhanced mode command series using query operator:
“*CLS?”
(Clear the error queue. Wait for reply)
“UNIT? KPA”
(Generates a reply. User must wait for reply before continuing)
“MMODE? A”
(Generates a reply. User must wait for reply before continuing)
“PS? 100”
(Generates a reply. User must wait for reply before continuing)
•
IEEE-488 enhanced mode commands without query operator:
“*CLS”
(Clear the error queue. No reply)
“UNIT KPA”
(No reply)
“MMODE A”
(No reply)
“PS 100”
(No reply)
“ERR?”
(Wait for reply. User should use
“ERR?”
query following a series
of non-query commands to check for errors that may have
occurred)
•
IEEE-488 enhanced mode multiple commands without query operator:
“*CLS”
(Clear the error queue. No reply)
“UNIT KPA;MMODE A;PS 100”
(Three commands at once. No reply)
“ERR?”
(Wait for reply. User should use
“ERR?”
query following a series of non-query
commands to check for errors that may
have occurred)
•
COM1 enhanced mode command:
“*CLS”
or
“*CLS?”
(Clear the error queue. Wait for reply)
“UNIT KPA”
or
“UNIT? KPA”
(Generates a reply. User must wait for
reply before continuing)
“MMODE A”
or
“MMODE? A”
(Generates a reply. User must wait for
reply before continuing)
“PS 100”
or
“PS? 100”
(Generates a reply. User must wait for
reply before continuing)
4.3.2.2
USING QUERY TYPE COMMANDS
The QUERY type of program message just requests data from the PPCH-G.
Placing the query operator
“?”
immediately after the command creates a query.
You
must
wait for a reply with a query. If you send any type of program message to
the PPCH-G after a query before receiving a reply, the program message will be
discarded and an error will be generated. Errors are reporting using the IEEE
Std. 488.2 status reporting model. A Query program message always ends with
a question mark. Most queries will return a reply within 200 ms except:
“PR?”
,
“PRR?”
,
“SR?”
,
“ATM?”
,
“RATE?”
: Up to 2 seconds.
“RPT”
,
“ARANGE”
: Up to 10 seconds
The syntax for using a QUERY program message is listed next to the keyword
“Query:”
in each program message summary in Section 4.4.4.
