User manual
*OPC — Operation Complete Set the OPC bit in the standard event status register after
all pending commands are complete
Description
On power-up or when the *CLS or *RST is executed, the Model 2000 goes into the Op-
eration Complete Command Idle State (OCIS). In this state, no pending overlapped com-
mands exist. The Model 2000 has three overlapped commands:
• :INITiate
• :INITiate:CONTinuous ON
•*TRG
When you send the *OPC command, the Model 2000 exits from OCIS and enters the Op-
eration Complete Command Active State (OCAS). In OCAS, the instrument continuously
monitors the No-Operation-Pending flag. After the last pending overlapped command is
completed (No-Operation- Pending flag set to true), the Operation Complete (OPC) bit in the
Standard Event Status Register sets, and the instrument goes back into OCIS.
Note that the instrument always goes into OCAS when *OPC is executed. If no pending
command operations are present (e.g. trigger model in idle state), the Model 2000 immedi
-
ately sets the OPC bit and returns to OCIS.
When used with the :INITiate or :INITiate:CONTinuous ON command, the OPC bit of the
Standard Event Status Register will not set until the Model 2000 goes back into the idle state.
The initiate operations are not considered finished until the instrument goes into idle.
When used with the *TRG command, the OPC bit will not set until the operations associ-
ated with the *TRG command (and the initiate command) are finished. The *TRG command
is considered to be finished when the Device Action completes or when operation stops a
control source to wait for an event (see Trigger Model in this section).
To use the *OPC exclusively with the *TRG command, first force the completion of the
initiate command so that only the *TRG command is pending. Do this by sending the :ABORt
command to place the instrument in idle, which (by definition) completes the initiate com-
mand. Since continuous initiation is on, operation continues on into the Trigger Model. After
sending the *TRG command, the OPC bit sets when the *TRG command is finished.
2000-900 (J - Aug 2010) BOOK.fm Page 44 Wednesday, October 12, 2011 12:29 PM