Casio QT-2000 Service Manual page 27

Pin No. Name
21 _KO7 Key common signal (KO7)
22 _KO6 Key common signal (KO6)
23 _KO5 Key common signal (KO5)
24 _KO4 Key common signal (KO4)
25 _KO3 Key common signal (KO3)
26 VSS GND
27 _KO2 Key common signal (KO2)
28 _KO1 Key common signal (KO1)
29 _KO0 Key common signal (KO0)
30 _INTPWD Power down signal
31 AD7 Address / Data bus (AD7)
32 AD6 Address / Data bus (AD6)
33 AD5 Address / Data bus (AD5)
34 AD4 Address / Data bus (AD4)
35 AD3 Address / Data bus (AD3)
36 AD2 Address / Data bus (AD2)
37 VSS GND
38 AD1 Address / Data bus (AD1)
39 VDD VDD
40 AD0 Address / Data bus (AD0)
41 _CRAM0 Chip select signal for system RAM
42 _CRAM1 Chip select signal for system RAM
43 _CRAM2 Nit used
44 CPUCLK Clock signal from CPU
45 ASTB Address strobe signal from CPU
46 _WR Write signal from CPU
47 _RD Read signal from CPU
48 ICEASTB GND
49 _RAM3 Bank select signal
50 NC Not used
51 VSS GND
52 _CRAM3 Not used
53 _RAM2 Bank select signal for RAM
54 _RAM1 Bank select signal for RAM
55 _RAM0 Bank select signal for RAM
56 _RESET Reset signal
57 _CSGA2 Chip select signal
58 _MEMWR Memory write signal
59 _INT Initilize signal
60 _REFRESH Not used
61 _MEMWRT Not used
62 RFSEL VCC
63 ITEST2 GND
64 ITEST1 GND
65 DIP8 Not used
66 DIP7 Not used
67 CASHSW6 Clerk switch signal
68 CASHSW5 Clerk switch signal
69 CASHSW4 Clerk switch signal
70 CASHSW3 Clerk switch signal
Description
— 25 —
I n / O u t
Out
Out
Out
Out
Out
-
Out
Out
Out
In
In/Out
In/Out
In/Out
In/Out
In/Out
In/Out
-
In/Out
In
In/Out
Out
Out
Out
In
In
In
In
In
In
-
-
Out
In
In
In
Out
In
In
Out
Out
Out
In
In
In
In
In
In
In
In
In