Casio QT-2100 Service Manual

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5-7. LCD CONTROLLER (IC4)
5-7-1. BLOCK DIAGRAM
5-7-2. Pin description
I/O
CONTROLLER
(IC11)
78 K IV
12.5 MHz
LCD
CONTROLLER
(IC4)
VRAM
BUS
Display memory
(IC1)
256 Kbit
A0-A15
DECODER
D0-D7
RD
WR
WAIT
MPUCLK (12.5 MHz)
IOCS
MEMCS
MCLK
6.00 Mhz
MCLK (LCD BUS CLOCK)
D0-D3
LCD
PIN NO NAME I/O DESCRIPTION PIN NO NAME I/O DESCRIPTION
1 DB7 I/O System data bus 51 VD7 I/O Display memory data bus
2 Vss GND 52 Vss GND
3 Vdd Vcc 53 Vdd Vcc
4 DB8 I/O Connected to Vdd 54 VD8 I/O Not used
5 DB9 I/O Connected to Vdd 55 VD9 I/O Not used
6 DB10 I/O Connected to Vdd 56 VD10 I/O Not used
7 DB11 I/O Connected to Vdd 57 VD11 I/O Not used
8 DB12 I/O Connected to Vdd 58 VD12 I/O Not used
9 DB13 I/O Connected to Vdd 59 VD13 I/O Not used
10 DB14 I/O Connected to Vdd 60 VD14 I/O Not used
11 DB15 I/O Connected to Vdd 61 VD15 I/O Not used
12 AB0 I System address bus 62 VA11 O Display memory address bus
13 AB1 I System address bus 63 VA12 O Display memory address bus
14 AB2 I System address bus 64 VA13 O Display memory address bus
15 AB3 I System address bus 65 O Display memory address bus
16 AB4 I System address bus 66 VA15 O Display memory address bus
17 AB5 I System address bus 67 VWE O Write signal for display memory
18 AB6 I System address bus 68 VCS0 O Select display memory
19 AB7 I System address bus 69 VCS1 O Not used
20 AB8 I System address bus 70 UD3 O Panel display data bus
21 AB9 I System address bus 71 UD2 O Panel display data bus
22 AB10 I System address bus 72 UD1 O Panel display data bus
23 AB11 I System address bus 73 UD0 O Panel display data bus
24 AB12 I System address bus 74 LD3 O Not used
25 AB13 I System address bus 75 LD2 O Not used
26 AB14 I System address bus 76 LD1 O Not used
27 AB15 I Connected to GND 77 LD0 O Not used
28 AB16 I Connected to GND 78 YD O Vertical scanning start pulse
29 AB17 I Connected to GND 79 LP O Display data latch clock
30 AB18 I Connected to GND 80 WF O Not used
31 AB19 I Connected to GND 81 XSCL O Display data shift clock
32 RESET I Reset signal 82 LCDENB O LCD enable signal output
33 VA0 O Display memory address bus 83 VOE O Read signal for display memory
34 VA1 O Display memory address bus 84 IOCS I Select internal registers
35 VA2 O Display memory address bus 85 IOW I Write signal for internal register
36 VA3 O Display memory address bus 86 IOR I Read signal for internal register
37 VA4 O Display memory address bus 87 MEMCS I Indicate a memory cycle
38 VA5 O Display memory address bus 88 MEMW I Indicate a memory write cycle
39 VA6 O Display memory address bus 89 MEMR I Indicate a memory read cycle
40 VA7 O Display memory address bus 90 READY O Ready signal
41 VA8 O Display memory address bus 91 BHE I Vcc
42 VA9 O Display memory address bus 92 OSC1 I Clock signal
43 VA10 O Display memory address bus 93 OSC2 O Clock signal
44 VD0 I/O Display memory data bus 94 DB0 I/O System data bus
45 VD1 I/O Display memory data bus 95 DB1 I/O System data bus
46 VD2 I/O Display memory data bus 96 DB2 I/O System data bus
47 VD3 I/O Display memory data bus 97 DB3 I/O System data bus
48 VD4 I/O Display memory data bus 98 DB4 I/O System data bus
49 VD5 I/O Display memory data bus 99 DB5 I/O System data bus
50 VD6 I/O Display memory data bus 100 DB6 I/O System data bus

Casio QT-2100 Specifications

General

Brand	Casio
Model	QT-2100
Category	Cash Register
Language	English