DLS DLS 400A, Operating Manual

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REMOTE CONTROL: COMMON COMMAND SET
IEE E
R S 232C
Page 71
bit 5 Command Error. Either a syntax error (order of command words) or a semantic
error (spelling of command words) has occurred. A GET (Group Execute Trig-
ger) or *TRG command will also set this bit.
bit 6 User Request. Indicates that the user has activated a Device Defined control
through the front panel. Not used, so this bit is always 0.
bit 7 Power on. This bit is set when the DLS 400 is turn on. Sending *ESR? clears the
bit and stays clear until the power is turned on again.
The setting of the Event Status Register can be read with the Event Status Register query
command (*ESR?). This will put the value of the register in the output queue, AND will
clear the register.
8.2 DLS 400 Synchronization
The program controlling the DLS 400 can use three different commands to synchronize
with the DLS 400: *OPC, *OPC? and *WAI. Following are the main differences:
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 communi-
cation with the DLS 400 until all pending operations are completed.
Set
Operation
Complete bit
when Done
Return “1”
when
operation
complete
Raise SRQ
when
operation
complete
Block
comm. with
the
NSA 400J
Required
Enable Bit(s)
*OPC Yes No
Yes
1
No
Operation Com-
plete, ESB
*OPC? No Yes
Yes
2
No MAV
*WAI No No No Yes none