Chapter 5
S Mode Functions
© National Instruments Corp.
5-53
GPIB-232CT User Manual
tmo - Change or Disable Time Limit
Type:
Initialization
function
Syntax:
tm
o [timeio][,timesp]
<CR>
Purpose:
You
use
tmo
at the beginning of your program to change the
time limits in effect on the GPIB-232CT. The time limits
prevent the GPIB-232CT from hanging indefinitely when
waiting for critical events to occur.
Remarks:
The
arguments
timeio
and
timesp
are numeric strings.
timeio
specifies the amount of time in seconds the
GPIB-232CT waits for an I/O operation (
rd
,
wrt
,
cmd
) or
the
wait
function to complete.
timesp
specifies the
amount of time in seconds each device is given in which to
respond to a serial poll. The power-on timeouts are 10
seconds for
timeio
and 1/10 of a second for
timesp
.
timeio
and
timesp
can be any decimal number between
.00001 and 3600, which corresponds to time limits between
10 microseconds and 1 hour.
10,.1
specifies a time of 10
seconds for I/O operations and 1/10 of a second for serial poll
response.
timeio
and
timesp
can also be 0, which
disables either timeout accordingly. Neither
timeio
nor
timesp
can contain commas.
The
timeio
time limit is in effect for the
cmd
,
rd
, and
wrt
functions. If the GPIB-232CT cannot complete any of these
functions within the period of time set by
timeio
, it aborts
the function and records the EABO error. Bytes that were
transferred before the timeout are not affected.
The
timeio
time limit is also the maximum amount of time
the wait function waits when you call it with the TIMO bit set
in the
wait
mask.
The
timesp
time limit is in effect only for the
rsp
function.
If a polled device fails to respond within the amount of time
indicated by
timesp
, the GPIB-232CT returns an error flag.
