Omega OMB-PER-488/W95, User Manual

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112 API Command Reference Personal488 User's Manual For Windows95 and Windows NT
TimeOut
Syntax
INT WINAPI TimeOut(DevHandleT devHandle, DWORD millisec);
devHandle refers to either an IEEE 488 interface or an external device.
millisec
is a numeric value given in milliseconds.
Returns
-1 if error
Mode
Any
Bus States
None
Example
errorcode = TimeOut(ieee,100); Sets the timeout value to 100 msec.
See Also
TimeOutQuery, Reset
The
TimeOut
command sets the number of milliseconds that Driver488 waits for a transfer before
declaring a time out error. Driver488 checks for timeout errors on every byte it transfers, except in the
case of asynchronous transfers. While the first byte of an asynchronous transfer is checked for time
out, subsequent bytes are not. Your program must check for timely completion of an asynchronous
transfer.
Time out checking may be suppressed by specifying a time out value of zero seconds, which specifies
an infinite timeout. The default time out is specified in the startup configuration, normally
10
seconds.
The time out interval may be specified to the nearest
0.001
seconds (1 millisecond). However, due to
the limitations of the computer, the actual interval is always a multiple of
55
milliseconds and there is
an uncertainty of
55
msec in the actual interval. Time out intervals from
1
to
110
milliseconds are
rounded to
110
milliseconds. Larger intervals are rounded to the nearest multiple of
55
msec (e.g.
165
,
220
,
275
msec, etc.).