Yamaha GX-900 Service Manual page 52

GX-900
IC2 : M30622M8-xxxFP [P.C.B. MD]
Main System Microprocessor (MD CPU)
No. Port
35 P63/TxD0
36 P62/RxD0
37 P61/CLK0
38 P60//CTS0,/RTS0
39 P57//RDY,CLKout
40 P56/ALE
41 P55//HOLD
42 P54//HLDA
43 P53/BCLK
44 P52//RD
45 P51//WRH,/BHE
46 P50//WRL,/WR
47 P47//CS3
48 P46//CS2
49 P45//CS1
50 P44//CS0
51 P43/A19
52 P42/A18
53 P41/A17
54 P40/A16
55 P37/A15
56 P36/A14
57 P35/A13
58 P34/A12
59 P33/A11
60 P32/A10
61 P31/A9
62 Vcc
63 P30/A8
64 Vss
65 P27/A7
66 P26/A6
67 P25/A5
68 P24/A4
69 P23/A3
70 P22/A2
71 P21/A1
72 P20/A0
73 P17/D15
74 P16/D14
75 P15/D13
76 P14/D12
77 P13/D11
78 P12/D10
79 P11/D9
80 P10/D8
81 P07/D7
82 P06/D6
83 P05/D5
84 P04/D4
85 P03/D3
86 P02/D2
87 P01/D1
88 P00/D0
89 P107/AN7
90 P106/AN6
91 P105/AN5
92 P104/AN4
93 P103/AN3
94 P102/AN2
95 P101/AN1
96 AVss
97 P100/AN0
98 Vref
99 AVcc
100 P97//ADTRG
51
I/O Name
O KDATA MD key data
I MDDATA MD data input
O DSCK MD clock output
O MD-ST MD start (MD-ON)
O /MD-RES MD reset output
I/O Unused (GND)
I SEARCH Unused (GND)
O PDOWN Used at MD unit power failure
I/O Unused (GND)
I/O Unused (GND)
I/O Unused (GND)
I/O Unused (GND)
I/O Unused (GND)
I MODEL Model input
I Ver Destination input
I /LOADIN H-L: DISC IN
I/O Unused (GND)
I/O Unused (GND)
I/O Unused (GND)
I/O Unused (GND)
I/O Unused (GND)
I/O Unused (GND)
I/O Unused (GND)
I/O Unused (GND)
I/O Unused (GND)
I/O Unused (GND)
I/O Unused (GND)
I VCC Microprocessor power supply input
I/O Unused (GND)
I GND GND level input
I/O Unused (GND)
I/O Unused (GND)
I/O Unused (GND)
I/O Unused (GND)
I/O Unused (GND)
I/O Unused (GND)
I/O Unused (GND)
I/O Unused (GND)
I/O Unused (GND)
I/O Unused (GND)
I/O Unused (GND)
I/O Unused (GND)
I/O Unused (GND)
I/O Unused (GND)
I/O Unused (GND)
I/O Unused (GND)
I/O Unused (GND)
I/O Unused (GND)
I/O Unused (GND)
I/O Unused (GND)
I/O Unused (GND)
I/O Unused (GND)
I/O Unused (GND)
I/O Unused (GND)
I/O Unused (GND)
I/O Unused (GND)
I/O Unused (GND)
I/O Unused (GND)
I/O Unused (GND)
I/O Unused (GND)
I/O Unused (GND)
I DGND GND level input for AD
I/O Unused (GND)
I VREF Open
I ADVCC Open
I/O DITMUTE Mute output to DIT
Function