Using The Scan Complete Bit; Example: Scan Complete Interrupt - HP E1366A User Manual

Using the Scan Complete Bit

Example: Scan
Complete Interrupt
36 Understanding the HP E1366A/E1367A RF Multiplexers
You can use the Scan Complete Bit (bit 8) in the Operation Status register
of a switchbox to determine when a scanning cycle completes (no other bits
in the register apply to the switchbox). Bit 8 has a decimal value of 256 and
you can read it directly with the
STATus:OPERation[:EVENt]?
When enabled by the
STAT:OPER:ENAB 256
Bit will be reported as bit 7 of the Status register. Use the HP-IB Serial Poll
or the IEEE 488.2 Common Command
When bit 7 of the Status register is enabled by the
Command to assert an HP-IB Service Request (SRQ), you can interrupt the
computer when the Scan Complete Bit is set, after a scanning cycle
completes. This allows the controller to do other operations while the
scanning cycle is in progress.
The following example monitors bit 7 in the Status register to determine
when the scanning cycle completes. The computer used in this example is
an HP 9000 Series 200/300 used with HP BASIC as the programming
language. The computer interfaces with an HP E1300A/E1301A mainframe
over HP-IB. The HP-IB select code is 7, the HP-IB primary address is 09,
and the HP-IB secondary address is 15.
10 OUTPUT 70915;"*CLS"
20 OUTPUT 70915;"STAT:OPER:ENAB 256" ! Enable Scan Complete Bit to
30 OUTPUT 70915;"*SRE 128"
40 OUTPUT 70915;"TRIG:SOUR EXT"
50 OUTPUT 70915;"SCAN (@100:105)" ! Select channels to be scanned
60 OUTPUT 70915;"INIT"
70 WHILE NOT BIT(SPOLL(70915),7)
80 PRINT "DO OTHER OPERATION HERE" ! Enter program lines for
90 END WHILE
100 PRINT "INTERRUPT GENERATED" ! Program goes to this line after
110 END
STAT:OPER? command. Refer to
command in Chapter 5 for an example.
command, the Scan Complete
*STB? to read the Status register.
*SRE 128
! Clear all switchbox status structure
set bit 7 in Status register
! Enable bit 7 of Status register to
assert SRQ
! External trigger mode
! Start scanning cycle
! Waiting for scan complete
computer to do other operations
interrupt generated by a completed
scanning cycle
Common
Chapter 4