Measurement Computing Personal488 rev.3.0 For DOS & Windows 3.Xi - Manual (Page 329)

15B. Driver488/SUB, W31, W95, & WNT III. COMMAND REFERENCES - 15. Command References
III-314 Personal488 User’s Manual, Rev. 3.0
Abort
SYNTAX int pascal Abort(DevHandleT devHandle);
devHandle refers to either an IEEE 488 hardware interface or an external device.
If devHandle refers to an external device, the Abort command will act on
the hardware interface to which the external device is attached.
RETURNS -1 if error
MODE SC or *SC
•CA
BUS STATES IFC, *IFC (SC)
ATN
•MTA (*SCCA)
SEE ALSO SysController
EXAMPLE errorflag = Abort(ieee);
As the System Controller ( SC ), whether Driver488 is the Active Controller or not, the Abort command
causes the Interface Clear ( IFC ) bus management line to be asserted for at least 500 microseconds. By
asserting IFC , Driver488 regains control of the bus even if one of the devices has locked it up during a
data transfer. Asserting IFC also makes Driver488 the Active Controller. If a Non System Controller
was the Active Controller, it is forced to relinquish control to Driver488. Abort forces all IEEE 488
device interfaces into a quiescent state.
If Driver488 is a Non System Controller in the Active Controller state ( *SC
•CA ), it asserts Attention
( ATN ), which stops any bus transactions, and then sends its My Talk Address ( MTA ) to “Untalk” any
other Talkers on the bus. It does not (and cannot) assert IFC .
Arm
SYNTAX int pascal Arm(DevHandleT devHandle, ArmCondT condition);
devHandle refers to either an IEEE 488 hardware interface or an external device.
If devHandle refers to an external device, the Arm command acts on the
hardware interface to which the external device is attached.
condition is one of the following: acError, acSRQ, acPeripheral,
acController, acTrigger, acClear, acTalk, acListen,
acIdle, acByteIn, acByteOut, or acChange .
RETURNS -1 if error
MODE Any
BUS STATES None
SEE ALSO Disarm, OnEvent, LightPen
EXAMPLE errorflag = Arm(ieee, acSRQ|acTrigger|acChange);
The following Arm conditions are supported:
Condition Description
acSRQ The Service Request bus line is asserted.
acPeripheral An addressed status change has occurred and the interface is a Peripheral.
acController An addressed status change has occurred and the interface is an Active Controller.
acTrigger The interface has received a device Trigger command.
acClear The interface has received a device Clear command.
acTalk An addressed status change has occurred and the interface is a Talker.
acListen An addressed status change has occurred and the interface is a Listener.
acIdle An addressed status change has occurred and the interface is neither Talker nor Listener.
acByteIn The interface has received a data byte.
acByteOut The interface has been configured to output a data byte.
acError A Driver488 error has occurred.
acChange The interface has changed its addressed status. Its Controller/Peripheral or
Talker/Listener/Idle states of the interface have changed.