Оценок - 0, средний балл: 0
(
)
)
|
К этому устройству также есть другие инструкции:
Фрагмент инструкции
the
in
terrupt
o ccurs
do es
not
complete
the
I/O.
A
CCL
is
returned,
and
FCHECK
returns
the
message,
FSERR
79--NO
NOWAIT
I/O
PENDING
FOR
SPECIFIED
FILE.
If
the
FREAD
in
trinsic
w
as
called
b efore
FCONTROL
with
a
con
trolco de
of
48
Note
w
as
in
v
ok
ed,
it
w
ould
ha
v
e
b een
handled
as
a
normal,
non-softw
are
in
terrupt
FREAD .
MPE/iX
starts
out
with
softw
are
in
terrupts
disabled.
If
the
FREAD
is
satised,
the
softw
are
in
terrupt
is
p ostp
oned
un
til
in
terrupts
are
explicitly
enabled.
The
pro cess
uses
FINTSTATE
at
this
p oint
to
enable
softw
are
in
terrupts
for
all
\armed"
les
op ened
b
y
this
pro cess.
This
includes
all
les
curren
tly
armed,
and
an
y
y
et
to
b e
armed
b
y
this
pro cess,
un
til
FINTSTATE
is
called
to
disable
in
terrupts.
The
call
to
FINTSTATE
can
o ccur
an
ywhere
in
this
sequence,
but
the
other
in
trinsic
calls
should
b e
made
in
the
order
given.
Interrupt
Handler
The
in
terrupt
handler
is
a
sp ecial
pro cedure
of
the
pro cess,
dev
oted
to
completing
the
I/O
request
after
an
in
terrupt
o ccurs.
This
pro cedure
is
nev
er
called
explicitly
.
Instead,
MPE/iX
in
v
ok
es
the
in
terrupt
handler
when
a
softw
are
in
terrupt
o ccurs,
p ossibly
from
the
middle
of
a
statement.
The
pro cedure
declaration
can
b e
either
without
parameters,
or
ha
v
e
a
single
INTEGER
parameter
in
to
whic
h
MPE/iX
puts
the
le
n
um
b er.
The
le
n
um
b er
parameter
of
the
softw
are
in
terrupt
handler
is
useful
if
there
are
sev
eral
les
sharing
the
same
softw
are
in
terrupt
handler
pro cedure
and
some
require
sp ecial
handling.
F
or
example,
eac
h
le
may
ha
v
e
a
dieren
t
buer
address
passed
to
IOWAIT .
MPE/iX
automatically
disables
softw
are
in
terrupts
and
CONTR
OL-Y
traps
when
it
jumps
to
the
in
terrupt
handler.
A
call
to
IODONTWAIT
or
IOWAIT
is
needed
to
nish
the
I/O
request.
The
I/O
request
can
b e
completed
immediately
,
so
IOWAIT
and
IODONTWAIT
will
w
ork
the
same
w
a
y
.
( IOWAIT
alwa
ys
completes
immediately
.)
Chec
k
the
condition
co de
(a
go
o d
idea
after
an
y
in
trinsic
call).
CCG
means
the
in
terrupt
o ccurred
b ecause
of
an
End-Of-File
condition.
If
a
CCE
is
returned,
the
pro cess
has
a
record.
It
can
b e
pro cessed
here,
or
a
ag
can
b e
set
to
indicate
that
the
record
has
b een
receiv
ed
and
should
b e
handled
during
the
normal
non-in
terrupt
pro cessing.
Often,
at
this
p oint,
the
next
softw
are
in
terrupt
read
is
set
up
b
y
p erforming
another
FREAD ,
if
the
pro cess
w
an
ts
to
con
tinue
to
see
new
records
written
to
this
message
le.
The
FREAD
do es
not
ha
v
e
to
b e
done
here
and
could
b e
p erformed
elsewhere
during
normal
pro cessing.
The
pro cess
may
not
w
an
t
to
issue
an
y
FREAD
at
all,
if
the
command
just
receiv
ed
w
as
to
stop
immediately
and
terminate.
The
last
statement
in
the
in
terrupt
handler
m
ust
b e
a
call
to
FINTEXIT .
This
allo ws
the
pro cess
to
pic
k
up
where
it
left
o
when
the
in
terrupt
o ccurred,
enable
CONTR
OL-Y
traps,
and
optionally
leav
e
softw
are
in
terrupts
enabled
or
disabled.
If
this
call
is
omitted,
the
pro cess
may
nev
er
get
bac
k
to
where
it
w
as
b efore
the
in
terrupt.
Exiting
with
softw
are
in
terrupts
enabled
is
usual,
but
the
pro cess
may
leav
e
them
disabled
if
the
record
needs
sp ecial
pro cessing
and
it
do es
not
w
an
t
an
y
additional
in
terrupts
un
til
it
is
completed.
A
t
that
time
it
needs
to
call
FINTSTATE
to
enable
in
terrupts.
Softw
are
Interrupts
6-3
...Эта инструкция также подходит к моделям:
Программное обеспечение - MPE/iX 6.5 Operating System (249.34 kb)
Программное обеспечение - MPE/iX 7.0 Operating System (249.34 kb)
Программное обеспечение - MPE/iX 7.5 Operating System (249.34 kb)