Spirent DLS 6700, Руководство по эксплуатации

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Chapter 4: REMOTE CONTROL
Spirent Communications
7104000557
Page 4-11
4.6.3 DLS 6700 Synchronization
The program controlling the DLS 6700 can use three different commands to synchro-
nize with the DLS 6700: *OPC, *OPC? and *WAI. The main differences are as follows:
1 if “Operation Complete” and ESB are enabled.
2 if MAV is enabled.
The main difference between OPC and WAI is that WAI will block any further commu-
nication with the DLS 6700 until all pending operations are completed.
The main difference between *OPC and *OPC? is that *OPC sets the “Operation Com-
plete” bit, and *OPC? will return an ASCII “1” when all pending operations are com-
pleted.
Make sure that all the required enable bits are set.
When using *OPC or *OPC?, the program controlling the DLS 6700 can determine
when the operation is completed by waiting for SRQ, or by reading the status byte
with the serial poll or with *STB? (if corresponding bits are enabled).
If the program uses the *OPC? command and then sends more queries, the program
must be ready to receive the “1” concatenated to other responses at any time. When
using *WAI, the communication time out should be set long enough to avoid losing
data (the DLS 6700 needs approximately 2 seconds to set a loop).
Set Opera-
tion Com-
plete bit
when done
Return “1”
when oper-
ation com-
plete
Raise SRQ
when oper-
ation com-
plete
Block
comm. with
the
DLS 6700
Required
Enable
Bit(s)
*OPC Yes No
Yes
1
No Operation
Complete,
ESB
*OPC? No Yes
Yes
2
No MAV
*WAI No No No Yes none