Example:
WAIT
655
STOP
will
cause the message
BREAK
IN
655 to
be
printed.
The
WAIT
statement halts program execution until a memory location
becomes non-zero.
Format:
WAIT
{address.
mask
address. mask. xor
where:
address
mask
xor
is
a memory address.
is
a one-byte mask value.
is
a one-byte mask value.
The
WAIT
statement does the following:
1.
Fetches the contents of the addressed memory location.
2.
Exclusive-ORs the value obtained in step 1
with
xor. if present. If xor
is
not
specified. it defauIts to
O.
When
xor
is
O.
this step
has
no effect.
3.
ANOs the value obtained in step 2
with
the specified mask value.
4.
If the result
is
O.
WAIT
returns ta step
1.
remaining in a loop that halts
program execution at the WAIT.
5.
If the result
is
not
O.
WAIT
processing
is
completed and program execu-
tion continues
with
the next statement following the
WAIT
statement.
The keyboard
STOP
key cannat interrupt execution of a
WAIT
statement.
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