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a,ixed type i.e. a disc with a mixture of data
a
nd
analogue audio
or
other non-data
si&nals. When the initiator tries lo
re
ad
from
1he non-
da111.
areas
the media
error
sense key
will
be returned
o41H#lhrwrir,ror
Hardwa
re
error
detected
in
1he sys1em.
·--
This
,S
relumed
when an illegal or non-existing command is
given, and
also
applies
to the specific bits in the command.
This
means
that the target has a boned the
C0111mand.
Thi$
means
that
an
attempt has been
ma
de
to read oulsidc the
volume
associated
wilh
the specified
logic unit
or the
logical
block
number
excireds.
1he
number
o
f blocks
associated
with that
volume.
GKOt:t'
t,1Vt:N1>0K- llt'illOl"t:1
COMMA:,,r/l>S
The
fonnat
of
a Group
6
command descrip1or
bkxk
is
as
folk,ws:
(MSbil)
(LS
bit)
0
·'
Byte
0
Groupcode(O)
Command
code
Logic
unit number
notused(O)
notused(O)
notLJsed(O)
No.ofdata
blockstotransfer
(
I)
Controlbyie(O)
1lte
group
code
+
the
command code
together
form
the operation
rode.
The
vendor-Llnique
bits, reserved
bits,
flag bil
aOO
link
bit are not
supponed
and
should
be set to zero.
The
Group
6 (vendor-unique)
commands
supported by
LV-DOS
are
as
foflows·
Bytt:O
C..-.d
aaae
(
~ t O d e )
CA
WriteF-<Odecommand
C8
ReadF-<Odereply
F-oode commands
a llow
the
initiator
to control
the LaserVi$ion player.
Some
ol
lhese
command$
return an
11.cknowledpmenl
or
reply
code.
Some relum
the
rep
ly
code
a]moo;t immediately while
o thers
return
it
up
10 several iCConds
later.
The
F-code
commands a
nd the
reply codes
are
sent through the SCSI
bus using
vendor-unique
read/write
commands..
CAHWrkeF~coamud
This
command allows
the initiator to
write
an
F-oode
to
a
s.pecific
logic
unit.
A
Mt.I
oDt
phase is required. in which
the F-a>de
command is
sent
a
nd
te
rminated
by
a
·CR'
character
:and
nullpadikd until
lhe
end
oflltcblod.
If there
are piceure
numbers in the F-codecommand,
then
these
picture
numbers
are constdererl to
be
logical picture numbers.
They
are
numbered from
uro
at
the
beginning
o
f the picture
Y()!umc
un1il
the
e
nd
of
the
volume.
regardles.s
oft
he
physical location
of
the volume on
1hedisc.
LV-00S
add,
the
offset between
the logical
pic:tureOa
nd1he
phy,ical
picture
address of
1ha1 volume
.
This
allo'NS
volumes
with
a
specific
LV-
ROM
a
pplication to
be placed
a
nywhere
o
n
a
new
disc
wilhout
h.1ving
to change
the
application
and retrieval programs
running on
the
initiator.
The
allocation of logical
pictures to a volume applies only to
pic:ture
numbers,
no1
lo
cha
pter numbers. This means that
gc,to picture
commands
will
be
executed with a modified picture number. chapter
commands
are
no
t
modified.
The F-code command
'?F
re
lums lhe
physical
picture
number
and
not the logical picture number in
order lo
avoid the probknu
ol
negative
picture numbers
or exceeding
volu
me
boundaries.
If
a
lo&.ic unit
is
open,
lhen
lo&.ical picture O
is the ril"1!t
physica1
picture
of the
corresponding volLJme.
Aei:eu
10a
logic
unit that
has
no
volume
associated
with it,
as
defined
by
'unit
not ready·,
is
not
considered
as an
enor.
This
,1llows
lhe
initialor to
ronlrol video
di~
without
LV-
ROM
d11.t11.
recorded
on
them. In
this case
L
V-DOS
is
fully
transparent and
will
no1
modify
lhe
picturenumbeD.
Nt11r: If
an F-code
reply
is
needed,
it
must
be
read
before another
F-code
command i$ Mued
lo
the same
logic unit.
Otherwise
the
reply
willbelo5t.
This
command
al' ° -
the
initiator to read
the
reply code
fro
m
che
reply
code buffer
for
the
specified
logic unit in
L\1-00S.
If
there is a reply
code
from
the player
then
the reply
code is
sent;
it
is
terminated
by
a
·cR·
character and null
padded until
the end
of
the
block.
Uthere
isno
reply
code
the
first
character of
the
block
is a ·CR' character.
A
dMI.
ii,
phutisneccssal")'.
If
lhe
reply
code
is rod from
the reply buffer in LV-OOS
then
lhe
bu
ffer fm
thac
~ c
u ni1
is
cleared.
If
a new F-code command
is
~nl
to
the p
layer
wit hoot reading the
reply
code of the previous command,
ii
will
be
erased
and the
new
reply
code
made
available
. L
V-DOS
keeps
a
reply
code
buffer
and
reserve$lhe
reply code
for
each logk
unil.
Nole:
Thi$
command
is
simila
r to the Group O Read
comma
nd; lhe
diffe renc,r
isonlylhat
the
operation
code is
vendor-unique, the
lramfer
leng1his
one
bkick
and
the
logica laddressofthe
blockiszero.
In addition
10 1he F-oode
command
list, there
are
2 commandl
1ha1
control
1he
way
digital
data
is
accessed
from
disc. The Fau
read
command
will
read data
from disc
and
will
stop
at the position on
the
disc where
Che pre
~ s
data was
read. The
Slow
rod
command
will
re1urn
to
the
picture
that
was
displayed
immediately
before 1he read
comma
nd
was
is.sued.
L
\I-DOS
fim reads
the
current pictu
re
number.
perfonns
the
data read and
transfer,
and will
then
return
to thal
picture
again.
While lhe
fil'SI
results
in
a
h
igherperform11.nce,
the
la.Iler
maybe
more
convenient
in
a
multi-initiator
environment. L V-DOS fflay
be
in
either of
these lwo
modes; the Fast
read
and Slow
read commands
being
a toggle
between the two
modes.
The
default
mode a
t
stan-up
is
RI.
SLOWNt:AU
Syalu:
RO
Flnltollle:
R(82D,,.
S2H)
Reapome:
None
Flulcdoa:
Slow
read
mode,
wi1hpic1ure restore afte
r search
Videoswitchedon after search,
40
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