334 Chapter5
Programming
Monitoring System Operation
The Service-Request Mask
The service-request mode is enabled and controlled by the
request-service-condition command, RQS. It defines a service-request
mask that specifies which of the status-byte bits can generate a service
request. Below, RQS specifies the ERROR-PRESENT and
COMMAND-COMPLETE states (bits 5 and 4, respectively) for service
requests.
OUTPUT 718;"RQS ";DVAL("00110000",2)
Selects bit 5 and 4
(32+16) to enable
service request mode for ERROR-PRESENT and COMMAND-COMPLETE.
OUTPUT 718;"RQS 48;"
Also selects bits 5
and 4 as above, but is somewhat easier to read.
Once RQS is executed, the analyzer requests service by setting the SRQ
line true when the desired conditions or events occur.
Computer Interrupt Statements
Now that the spectrum analyzer is prepared to trigger service requests,
you must prepare the computer to accept this type of interrupt. Use the
BASIC statements ON INTR…GOTO or CALL or GOSUB and
ENABLE INTR. ON INTR…GOTO causes the computer to branch to a
subroutine or some other part of the program when an interrupt is
generated. ENABLE INTRenables the computer to accept an interrupt.
These two commands appear below.
10 OUTPUT 718;"RQS 16;"
20 ON INTR 7 GOSUB Srq
30 ENABLE INTR 7;2
Table 5-4 Status Register
Bit Number Decimal
Equivalent
Analyzer
State
Description
7 128 Not used
6 64 RQS Requests service
5 32 ERROR
PRESENT
Set when error present
4 16 COMMAND
COMPLETE
Any command is completed
3 8 Not used
2 4 END OF
SWEEP
Set when any sweep is
completed
1 2 MESSAGE Set when display message
appears
0 1 TRIGGER Trigger is activated
To Next Page
Loading...
Need help?
General
