Agilent Technologies 33120A, Руководство пользователя

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Using *STB? to Read the Status Byte
The
*STB?
(status byte query) command is similar to a serial poll but it
is processed like any other instrument command. The
*STB?
command
returns the same result as a serial poll but the “request service” bit
(bit 6)
is not cleared if a serial poll has occurred.
The
*STB?
command is not handled automatically by the
IEEE
-488 bus
interface hardware and will be executed only after previous commands
have completed. Polling is not possible using the
*STB?
command.
Executing the
*STB?
command does not clear the Status Byte summary
register.
Using the Message Available Bit (MAV)
You can use the Status Byte “message available” bit (bit 4) to determine
when data is available to read into your bus controller. The function
generator subsequently clears bit 4
only after all messages have been read
from the output buffer.
To Interrupt Your Bus Controller Using SRQ
1 Send a device clear message to clear the function generator’s
output buffer (e.g.,
CLEAR 710
).
2 Clear the event registers with the
*CLS
(clear status) command.
3 Set up the enable register masks. Execute the
*ESE
command to set up
the Standard Event register and the
*SRE
command for the Status Byte.
4 Send the
*OPC?
(operation complete query) command and enter the
result to ensure synchronization.
5 Enable your bus controller’s
IEEE
-488
SRQ
interrupt.
4
Chapter 4 Remote Interface Reference
The SCPI Status Registers
205