Pioneer PX-7 Service Manual page 55

PX,
Test Details
(0)
Aging Test
[RAM
TEST]
00H,
55H AAH,
and
FFH
data
is
written within
the
COOOH
thru
DFFFH
and 8000H
thru
BFFFH
RAM
address
ranges,
and
the
written data
is
subsequently checked
to see that
it
matches
the
read
data.
* Since the
EOOOH
thru
FFFFH
address range
forms the
BASIC work
area,
it
cannot be
checked
by
this
test.
The INSPECTION
2
cartridge
must be used
if
a check
is
desired.
[ROM
TEST]
1.
The
total
sum
of data
in
all
addresses
(0000H
thru
7FFFH)
in
the
MSX-BASIC
ROM
(IC12)
is
checked
to see that
it
comes
to
2DH
(check
sum,
or addition of
all
bytes excluding
carry).
2.
The
total
sum
of data
in all
addresses
(4000H
thru
5FFFH)
in
the
P-BASIC
ROM
(IC13)
is
checked
to see that
it
comes
to
FFH.
[VRAM
TEST]
OOH, 55H,
AAH
and
FFH
data
is
written within
the
3800H
thru
3A98H
VRAM
address range, and
is
then compared
with
the read
data.
*
Since the screen
settings would be
destroyed,
it
is
not
possible to
check
all
addresses
by
this
test.
Again, the
INSPECTION
2
cartridge
must
be
used
if
a check
is
desired.
[VIDEO TEST]
First
the
16
color
bar,
and then
"all white",
are
displayed
on
the
screen.
[SOUND
TEST]
The L
channel,
R
channel, and
center
sounds
are
generated
in
that order.
(1)
Video
Test
The '"16 color bar",
"16
half bar",
"all
white",
and
"all
blue"
screen displays can
be
selected
by
numeral key
input.
This
test
is
used
in
video
sys-
tem
adjustments.
(Same
color
arrangement
as in
the
16
color
bar)
Fig.
11-5
16
half
bar
55