Yamaha SY77 Service Manual page 28

SY77
2.
TEST
2:
SYSTEM
RAM
TEST
t
02: RAK Read/tfrit'e
Performs
a read/write test of
RAM
oti
the following addresses.
IC127
:
40000h-47FFFh
IC128
:
48000h-4FFFFh
1C
1
29
;
BOOOOh -
57FFFh
1C
1
30
:
58000h - SFFFFh
{Only
1
024
bytes)
DISPLAY OF TEST RESULTS
Ql^
P*
02: RAH
Read/Write 4:ICI30 OK
(the
number
of the last-tested
1C)
or
NG
*
02:
RAH Read/tfrlle
«:IC*xx
HC
(where
n
=
RAM#
and xxx
=
IC#|
TEST
END
Ends
after
displaying the
results. All
RAM
data
Is
preserved.
3.
TEST
3:
SEQUENCER
ROM
TEST
*
03:
SEQtHCER
ROM
Performs a read
test
on the
ROM
(IC151)
of
DM1
circuit
board.
DISPLAY OF TEST RESULTS
OK
1
* 03:
SEOEKCER
ROM
OK
1
1
NG
*
03:
SEQENCER
ROM
KC
1
TEST
END
Ends
after displaying
the
results.
4.
TEST
4:
SEQUENCER
RAM
TEST
r
»
Of
:
SEqENCER
RAH
Performs
a
RAM
read/write test
on
all
addresses
of
IC153
(RAM
1),
IC158
(RAM
2)
and
IC159
(RAM
3).
DISPLAY OF TEST RESULTS
OK
t Of;
SEOEHCER RAH 123 OK
NG
t
04:
SEQEHCER RAH
ir3
HC
(e.g.
if
RAM
2
is
NG,
an
x
will
mark out the
RAM
2
n
it is
no
good.)
TEST END
Ends
after
displaying the
results. All
RAM
data
Is
preserved.
50
5Y77