National Instruments GPIB-PC - Manual (Page 159)

BASICA/QuickBASIC GPIB-PC Function Calls Section Four A
GPIB-PC User Manual 4A-84 ©National Instruments Corp.
BASICA/QuickBASIC BASICA/QuickBASIC
IBWAIT IBWAIT
Purpose: Wait for selected event
Format: CALL IBWAIT (BD%,MASK%)
Remarks: BD% specifies a device or an interface board. MASK% is a
bit mask with the same bit assignments as the status word,
IBSTA% . Each MASK% bit is set or cleared to wait or not
wait, respectively, for the corresponding event to occur.
The IBWAIT function is used to monitor the events
selected in MASK% and to delay processing until any of
them occur. These events and bit assignments are shown in
Table 4A.4.
IBWAIT also updates all conditions of the status word,
which may be read in the IBSTA% variable.
If MASK% =0 or MASK% =&H8000 (the ERR bit), the function
returns immediately.
If the TIMO bit is 0, or the time limit is set to 0 with the
IBTMO function, timeouts are disabled. Disabling timeouts
should be done only when setting MASK% =0 or when it is
certain the selected event will occur; otherwise, the
processor may wait indefinitely for the event to occur.