Sharp ER-A420 Manuel de service télécharger pdf (Page 13)

ER-A410U/ER-A420U HARDWARE DESCRIPTION

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6. KEY/DISPLAY

6-1. LCD CONTROL

The LCD control is the same for the ER-A410/ER-A420.

LCD-related Register

<Data Latch Signal> P94

L: LCD write data latch

6-2. KEY/DISPLAY SCAN

On the ER-A410/ER-A420, the key and display scan signal is common.

Key/display scan and key read are performed at the following timing.

Key/display scan cycle: 10ms

Blanking time: 50us

KEY DATA READ timing: 10 ~100us before turning off the strobe

signal

KEY DATA are read in two divisions by switching the exchange sig-

nal.

Key/Display-related Register

<LED Segment Signal> Write

<LCD Control Signal/Key Strobe Signal> Write

Bit3~0: KS3~0

At KS3~0, the strobe signals of KEY and POP UP Display are gener-

ated.

<Key Return Signal, Key Exchange Signal> Read Flat Keyboard

<Key Return Signal> Read Normal Keyboard

READ is performed at the timing of ST9 of CPU port P90 (Refer to 6-3.)

1: NORMAL KEY

0: FLAT KEY

The flat keyboard switches the key exchange signal and takes key data

in two times. For the reading timing, refer to the timing chart below.

The normal keyboard reads key data 10~100us before turning off the

strobe signal of the keyboard.

Function Address R/W

LCD Write Data 04001h W

LCD Read Data 04002h R

LCD Control Signal / Key Strobe Signal 04003h W

Data Latch Signal CPU port P94 W

Address Bit7 Bit6 Bit5 Bit4 Bit3 Bit2 Bit1 Bit0

04003h – E R/W RS KS3 KS2 KS1 KS0

Bit7: Not used

Bit6: E

Enable Signal Enable

Bit5: R/W

H: Data read L: Data Write

Bit4: RS

H: Data input L: Instruction Input

R/W

DB0-7

P94

DATA WRITE (CPU 3 LCD)

Valid Data

4003h

000xxxxx

WRITE

4001h

DATA

WRITE

4003h

010xxxxx

WRITE

4003h

000xxxxx

WRITE

4003h

001xxxxx

WRITE

R/W

DB0-7

P94

DATA READ (CPU 1 LCD)

Valid Data

4003h

001xxxxx

WRITE

4003h

001xxxxx

WRITE

CPU

P94

HIGH

4003h

011xxxxx

WRITE

4002h

DATA

READ

4003h

001xxxxx

WRITE

CPU

P94

LOW

Function Address R/W

LED Segment Signal 04000h W

LCD Control Signal / Key Strobe Signal 04003h W

Key Return Signal 04003h R

Key Exchange Signal 04003h Bit7 W

Key Select Signal CPU port P90 R

Address Bit7 Bit6 Bit5 Bit4 Bit3 Bit2 Bit1 Bit0

04000h dp g f e d c B a

Address Bit7 Bit6 Bit5 Bit4 Bit3 Bit2 Bit1 Bit0

04003h X E R/W RS KS3 KS2 KS1 KS0

Address Bit7 Bit6 Bit5 Bit4 Bit3 Bit2 Bit1 Bit0

04001h X X X X KR11 KR10 KR9 KR8

04003h KR7 KR6 KR5 KR4 KR3 KR2 KR1 KR0

Address Bit7 Bit6 Bit5 Bit4 Bit3 Bit2 Bit1 Bit0

04003h KR7 KR6 KR5 KR4 KR3 KR2 KR1 KR0

950m25us 50m5us

Max. 10us

10~100us

Fh Fh Fh

BLANK BLANKBLANK

1ST DIGIT

DISPLAY DATA

2ND DIGIT

DISPLAY DATA

1ST DIGIT

DISPLAY DATA

0 1 90

KS0~3

LED Segment

Signal

Key Return

Signal

1 2 ... 8 9 10 11 12 13 14 15 16 17 18 ... 43 44

Commentaires sur ces manuels

Chrisacend 30 Apr 2024 | 01:02:48

Hello, im noob :)

Sharp ER-A420 Manuel de service Page 13

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