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CHAIN COMMAND
6.4 -- Execution
Ope~ators
Word
Designato~
Error
Status
Wo~d
Part
W
Whole
~o~d
(bits o-F)
T
Error
T~pe
(bits 0-7)
M
Error Mask (bits 8-B)
5
Error Status (bits C-F)
0.4.4 SET
operator
The
SET
operator
can
be
used to place a certain bit
pattern into the system error status
wo~d.
In
pa~ticula~J
the SET operator is the only
~a~
that the Error Mask Flag can
be set to inhibit
CHAIN
process abortions.
The
MOOS
commands
will
only
set the Error Status and the Error Type.
The SET
operator has the following
~ormat:
where
<J/
is the status word designator (explained above) and
<valueJ is a hexadecimal
numbe~
that is to be placed into the
designated word part.
The
size
of
<value>
must
not
be
greater
than
the size of the word part into which the it is
to
be
placed.
If
the
status
word
designator
is
not
specified,
then
W,
the whole word part,
will
be assumed . .
If
<va
1
u
e:> i
s not s
p
e c
i
fie d
I
t h en z
e
row
i 11 b
e ass u
m,e
d .
As
an
example of the SET operatorl the following will set the
E~ror
Mask Flag Cbit B) to inhibit CHAIN process
aborting
due
to
command execution
e~rors:
@SET,M
8
@SET,W 800
@SET 800
All
three
Torms
will
set
bit B
of
the error status wordi
howevel'l
the last two forms wi
11,
in add
i
ti on,
set
to
zero
all
othe-r parts
of
the error statvs word.
6.4.5 TST operator
The
TST
operator
word Tor a
particular
following format:
is
used to examine the error status
condition.
This
operator
has
the
whe~e
<J}
is the status word designator, <condition>
is
the
test condition to be performed, and <value> is
a
hexadecimal
number that is used as pal't of the test.
Use
of
the
TST
ope~ato~
~esults
in
a
true or false
condition based on the test performed.
If
the result of
the
Page
06-11
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