Key-Display - Sharp XE-A40S Service Manual

PORT PIN No.
P107 89
POWER SUPPLY/CONTROL TERMINAL
PORT PIN No.
BYTE 8
CNVss 9
/RESET 12
Xout 13
Vss 14
Xin 15
Vcc 16
Vcc 62
Vss 64
Avss 96
Vref 98
Avcc 99

[5] KEY-DISPLAY

1. LCD CONTROL
1.1. LCD CONTROL
LCD-related registers
Function
LCD Write Data
LCD Read Data
LCD Control Signal
Data Latch Signal
1.1.1 LCD Control Signal / Key Strobe Signal
Address Bit7 Bit6 Bit5
04003h – E R/W
Bit7 : Not used
Bit6 : E
Enable Signal
Bit5 : R/W
H : Data read L : Data Write
Bit4 : RS
H : Data input L : Instruction Input
1.1.2 Data Latch Signal
L : LCD write data latch
I/O Pin name Signal name
O P107 LATCH
I/O Pin name
I BYTE Connected to VCC
I CNVss Connected to GND
I /RESET
O Xout Connected to XTAL
Vss Connected to GND
I Xin Connected to XTAL
Vcc Connected to VCC
Vcc Connected to VCC
Vss Connected to GND
AVss Connected to GND
Vref Connected to VCC
Avcc Connected to VCC
Address R/W
04001h W
04002h R
04003h W
CPU port P94 W
Bit4 Bit3 Bit2 Bit1 Bit0
RS – – –
Enable
Initial OFF
value MODE
L IN
Function
2. KEY/DISPLAY SCAN
On the XE-A40S, the key and display scan signal is common.
KEY/DISPLAY SCAN and key read should be performed at the follow-
ing timing.
1) KEY/DISPLAY SCAN cycle: 10ms
2) Blanking time: 50us
3) KEY DATA READ timing: More than 10 ms from the fall of the
SCAN signal
Key / Display-related registers
Function
LED Segment Signal
Key Strobe Signal
–
Key Return Signal
2.1. LED Segment Signal
Address Bit7
04000h dp
2.2. Key Strobe Signal
Address Bit7
04003h –
Bit3 ~ 0 : KS3 ~ 0
Strobe signals for keys and POP UP Display are generated at KS3 - 0.
2.3. Key Return Signal
PIN CPU
No. PORT
38 P60
37 P61
36 P62
35 P63
34 P64
33 P65
32 P66
31 P67
4 – 4
Function
PRINTER LATCH SIGNAL
Address
04000h
04003h
CPU port
Bit6 Bit5 Bit4 Bit3 Bit2
g f e d
Bit6 Bit5 Bit4 Bit3 Bit2
– – – KS3 KS2
Signal Function
name
KR0# KEY RETURN SIGNAL 0
KR1# KEY RETURN SIGNAL 1
KR2# KEY RETURN SIGNAL 2
KR3# KEY RETURN SIGNAL 3
KR4# KEY RETURN SIGNAL 4
KR5# KEY RETURN SIGNAL 5
KR6# KEY RETURN SIGNAL 6
KR7# KEY RETURN SIGNAL 7
XE-A40S
R/W
W
W
R
Bit1 Bit0
c b a
Bit1 Bit0
KS1 KS0