Casio AT-1 Service Manual page 9

Pin No. Terminal
1 ~ 8 CD0 ~ CD7
9, 10
11 GND7
12 CK16
13 VCC6
14 CK0
15 TCKB
16 VCC1
17 GND1
18, 19 XT0, XT1
20 SGL
21 CCSB
22 ~ 25 CA0 ~ CA3
26 CE0
27 CWRB
28 CRDB
29 ~ 32
33 RESB
34 TESB
35 ~ 39
40 ~ 49
RD0 ~ RD15
52 ~ 57
50 VCC2
51 GND2
58 RA23
59 RA22
60, 61 RA20, RA21
62 ~ 73
RA0 ~ RA19
75 ~ 82
74 GND5
83 WOK2
84 VCC3
85 GND3
86 WOK1
87 SOLM
88 SOLP
89 BOK
90 ~ 92
93 VCC5
94 EA14
95, 97
99 ~ 105
EA0 ~ EA12
107, 109
110, 112
In/Out
In/Out Data bus
Not used
In Ground (0 V) source
Out 16.384 MHz clock output
In +5 V source
In Clock input. Connected to terminal CK16.
Not used
In +5 V source
In Ground (0 V) source
In/Out 16.384 MHz clock input/output. Connected to a crystal oscillator.
In System control terminal. Single chip system: Open
In Chip select signal input
In Address bus
In Not used. Connected to ground.
In Write enable signal
In Read enable signal
Not used
In Reset signal input
In Not used. Connected to +5 V.
Not used
In Address bus for the sound source ROM
+5 V source
Ground (0 V) source
Out Not used
Out Chip select signal for the sound source ROM
Out Not used
Out Address bus for the sound source ROM
In Ground (0 V) source
Out Word clock output. Not used.
In +5 V source
In Ground (0 V) source
Out Word clock for the DAC
Out Serial data output. Not used.
Out Serial sound data output for the DAC
Out Bit clock output for the DAC
Not used
In +5 V source
Out Not used
Out Address bus for the effect RAM
— 7 —
Function