Isotech TTI 7 PLUS - RS-232 Interface Commands; Front Panel Operations

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TTI-7 Iss.02 – 06/11
*SRE <enable value>
Enables bits in the Service Request Enable Register. The selected bits are then reported to the Status Byte.
*SRE?
Queries the Service Request Enable Register. The instrument returns a decimal value which corresponds to the
binary-weighted sum of all bits set in the register.
*CLS
Clears the Status Byte Summary Register and all event registers, and also resets the Operation Complete Command
State and Operation Complete Query State.
*OPC?
This command sets the instrument’s ‘Operation Complete Query State’ active. When any ‘in-progress’ command is
completed, the state returns to idle, a ‘1’ is placed in the output queue and therefore the Message Available bit (4) is
set. The command should only be used in conjunction with non-query commands and is only available for IEEE.
Example
Data logging can take an appreciable time to execute, so it is useful to program the instrument to generate a service
request on completion of the logging function. The following command sequence can be used:
*SRE 16 Enables the Message Available bit to trigger a service request
*CLS Clears the Message Available bit
DATA:START Initiates data logging
*OPC? Sets RQS on completion of the log
Alternatively, the application programme can continuously poll the Message Available bit using *STB?.
The Status Byte Register can also be read by an IEEE-488.1 serial poll sequence.
RS-232 Interface Commands
SYSTem:LOCal
Return the instrument to the local mode from RS-232 operation. All keys on the front panel are fully functional. This
is the default at power-up.
SYSTem:REMote
Place the instrument in the remote mode for RS-232 operation. All keys on the front panel are disabled.
Front Panel Operations
The REMOTE legend indicates that the instrument is under control of the remote interface. The front panel keys will
be locked out.
The BUSY legend indicates that a measurement cycle is in progress. This is a particularly useful indication during
SINGLE trigger operations.
For the IEEE-488 interface, the ADDRESSED legend (“Adr”) indicates that the device has been addressed by the
system controller. Operation may be local or remote though.