Fluke 5790A, Руководство оператора

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5790A
Operators Manual
5-12
5-20. Using Commands
Communication between the controller and the 5790A consists of interface messages and
commands. Interface messages are defined by the IEEE-488.1 standard and control the
lowest level of bus communication. Interface messages are handled automatically by the
controller. (See "Interface Messages" further on in this section for more information.)
Commands are sent to the 5790A literally, for example, with the Fluke 1722A BASIC
PRINT statement. The commands are described in Section 6. There are three types of
commands:
Common commands: Commands that start with an asterisk. These are defined by the
IEEE-488.2 standard.
Device-dependent commands: Commands specific to the 5790A.
Queries: Commands that cause the 5790A to send a response to the controller. (These
commands always end with a question mark (?).)
A controller program first needs to initialize the interface and the 5790A.
Refer to following sample program:
10 INIT PORT 0 \ REMOTE @6 ! PUT THE 5790A INTO THE REMOTE STATE
20 PRINT @6, "INPUT INPUT2" ! MAKE INPUT2 THE ACTIVE INPUT
30 PRINT @6, "MEAS?" ! TAKE A MEASUREMENT
40 INPUT @6, V,F,ST ! GET THE RESULT
If you wish to use SRQs, first use the *SRE, *ESE, and ISCE commands to enable the
desired event. Refer to "Checking the Instrument Status" further on in this section for
more information.
You retrieve instrument parameters with a query (a programming command that ends
with a question mark):
200 PRINT @6, "DUNIT?" ! RETRIEVE DELTA UNITS
210 INPUT LINE @6, A$
220 PRINT "Delta Units are: "; A$
230 PRINT @6, "ONTIME?" ! RETRIEVE ON TIME
240 INPUT LINE @6, A$
250 PRINT "The instrument has been on for "; A$;" minutes"
This program generates the following sample output:
Delta Units are: PPM
The instrument has been on for 1595 minutes
Check for programming errors as in the following sample programs. Check the Error
Available (EAV) bit in the serial poll register using a serial poll.
300 A = SPL(6) ! CHECK FOR ERRORS
310 IF (A AND 8) THEN PRINT "There was an error"
320 PRINT @6, "*CLS" ! CLEAR ERRORS
Retrieve errors and explanations as follows. Since errors are accumulated in a queue, you
must read the entire queue to retrieve and clear all the errors.
400 PRINT @6, "ERR?" ! CHECK FOR ERRORS
410 INPUT @6, A, A$ ! READ IN THE ERROR
420 IF (A = 0) THEN GOTO 500 ! NO MORE ERRORS
430 PRINT "Error# :";A, A$ ! PRINT ERROR# AND EXPLANATION
440 GOTO 400
500 END