HP 8901B Operation And Calibration Manual page 146

Model 8901B
READ DATA
FROM 8 9 0 1 8
-
Operation
START 8 9 0 1 8
(-4
I
SET TRIQGER
MODE TO HOLD
I
( T 1 )
I
ENABLE SRO ON
DATA READY
( 2 2 . 3 S P )
I
CONF I QURE
I
MEASUREMENT A
TRIGGER MEASUREMENT
( T 2 , T 3 , GET OR
I
CLEAR KEY)
I
4 l
PROCESS OTHER
TEST OTHER 8 9 0 1 8
4No
1
SRO C O N D I T I O N S
I
READ DATA
FROM 8 9 0 1 8
I
1
I
1
RETURN FROM INTERRUPT
Figure 3-3. Example Flowchart Using the Service Request Message.
Using the Service Request Message.
The Service Request message can be used for detecting
instrument conditions and instrument or HP-IB code errors.
The Service Request Message can also be used for signaling measurement data ready. Remote
measurements are usually performed simply by triggering measurements, then reading the output data.
In certain applications, the controller must control other instruments while the
HP
8901B is making a
measurement. Using the instrument's ability to issue the Service Request message when data is ready,
frees the controller to process other routines until the Modulation Analyzer is ready with data.
See Figure 3-3, "Example Flowchart Using the Service Request Messagen for an example of using the
SRQ message to signal the controller that the HP 8901B has completed its measurement and the data
is
ready.
3-27