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3.8.2.7 Configuring the Control Signals
The 4863's control signals are configured with the CONFIGURE sub-
system. In the example, Clear is wired into the D/A to reset it to zero, Reset
is wired to the DPM to reset the meter at power turn-on time. Trigger could
be used by the DPM or it could be set to free run. The Status A input is
connected to 5 Vdc on the external board to monitor the external power
supply. Status B and the Remote output signal are not used in the example.
The example configure commands are:
e.g.
CONFigure:CLEar 0
'selects low true output
CONFigure:REMote 0
'selects low true output
CONFigure:RESet 0
'selects low true output
CONFigure:TRIGger 0
'selects low true output
CONFigure:ASTATus 1
'selects high true input
CONFigure:BSTATus 0
'selects low true input
3.8.2.8 Reading the Digital Input String
Now that the talk string has been defined and digital interface has been
configured, it is time to input data. Be sure that the external device is pulsing
the External Data Ready line or that talk handshaking is disabled. To read
the data with a command use the SENSe:DATA:PORT? or PI? query. Read
the response from the lower GPIB address or secondary address 00.
e.g.
CALL OUTPUT(dev, "SENSe:DATA:PORT?")
CALL ENTER(dev, Rdg$)
'Dual Primary address
example
or
CALL OUTPUT(dev+sec00, "SENSe:DATA:PORT?")
CALL ENTER(dev+sec00, Rdg$)
'Secondary address
example
For transparent data transfer, use the enter, input or receive command in
your GPIB command library to input the data from the upper primary
address if in the Dual Primary Address mode or from secondary address 01
if in the Secondary Address mode).
e.g.
CALL ENTER(dev+1, Rdg$)
'Dual Primary address
example
or
CALL ENTER(dev+sec01, Rdg$)
'Secondary address
example