Service Manual
r-
No.
1/0
Pin Name Function
50
0
CS2
CS2 output (GA, MPEG, other area 2 access)
51
0
CASL
DRAM CASL output
52
vss
Ground
53
l
TIOCAO
MPEG
A data transfer (DMA3) request input (edge detection)
54
0
RAS
DRAM CASL output
55
l/0
CS6
CS6
output (area 6 access)
56
-
NC
Not connected.
57
0
WRL
WRLoutput
58
0
WRH
WRH output
59
0
RD
RD output
60
0
RESET
GA reset output.
Lo: RESET, Hi: Release
61
- VSS
Ground
62
0
NC
Not conncted.
63
0
IRQOUT
Spare (Spare to output
"Lo"
during intenupt process)
64
I
TIOCAI
MPEG
V data transfer (DMA2) request input (edge detection)
65
0
NC
Not conncted.
66
0
DACKO
DMAO
(for CD-ROM sector data input) ACK output
(toGA)
67
I
DREOO
DMAO
(for CD-ROM sector data input)
REQ
input (from GA)
68
0
DACKI
DMA1 (for host data input/output) ACK output
(toGA)
69
I
DROOl
DMA1 (for host data input/output) REQ output (from GA)
70
-
vee
+SV
71
0
CK
SH-1
system clock output (20MHz)
(toGA)
72
-
VSS Ground
73
I EXTAL
A crystal oscillator
is
connected.
74
I XTAL
A crystal oscillator is connected.
75
-
vee
+SV
76
I NMI +SV
77
-
vss
Ground
78
-
NC
Not conncted.
79
I
RESET
Reset input (reset at
"Lo")
80
MOO
81
I
MDI MCU operation mode setting pins. The built-in
ROM
is
effective.
82
MD2
83
-
vee
+5V
84
-
vee
+5V
85
-
vee
+5V (power supply
of
analog circuits)
86
-
VREF +5V (analog reference power supply)
87
NC
88
NC
Ground (not used)
-
89
NC
90
NC
91
-
AVSS Ground (analog ground)
92
-
NC Ground (not used)
93 I VCD
·•
Input to detect whether VCD is connected
or
not.
Lo: CD drive connected, Hi: VCD connected.
94
-
NC
Ground (not used)
95
-
NC Ground
96
-
VSS Ground
97
I
MPEGAIRQ
MPEG A intenupt input (edge detection)
98
I
MPEGVIRQ
MPEG V intenupt input (edge detection)
99
-
vee
+5V
100 I
COMSYNC
CD
communications start signal input. Lo: Start, Hi: In the middle
101
I
COMREQ
CD
communications sync intenupt input (edge detection).
Lo: Duringclock transfer, Hi: During interval.
102 -
NC Not conncted.
103 - NC
Not conncted.
104
{"\
DEMP
Deemphasis output.
Lo:
DEMP OFF, Hi: DEMP
ON
'-'
105
-
NC
No conncted.
106
-
VSS
Ground
107
I CDATA
CD
communications data input
(SCKO
used)
108
0
HDATA
CD
communications data output (SCKO used)
109 I
TEST
Test control input.
Lo:
Test mode, Hi: Normal mode
110
0
TDATA
Test data output
Ill
0
COMCLK
CD
communications clock output (SCKO used)
ll2
0
TCLK
Clock output for test data
-64-