Sharp ER-A770 Service Manual download pdf (Page 51)

10. WAIT control

The weight control function built in the MPCA8 is used to provide an

interface with low-speed devices.

10-1. Block diagram

The block diagram of the wait control function is shown.

In the figure, the decoder, wait enabling register, AND-OR sections

are the same as those in the MPCA6 or 7, but other components are

newly incorporated in the MPCA7.

EXWAITZ and WAITZ are external weight signals which are to be

logically ORed inside the MPCA8 and output to the WAITZ. The

EXWAITZ is a general-purpose wait request terminal, and WAITZ is

the wait request signal from the VGA controller.

11. CKDC9

The ER-A770 on CKDC9 for the CKDC PWB and one CKDC9 for

POLE display (option) to carry out the following control operations.

CKDC PWB CKDC9:

• Clock (second data readable)

• Buzzer

• System reset

• Key/Clerk switch

POLE CKDC9(UP-P16DP or UP-I16DP)

• Customer display tube

11-1. Interface

CKDC9 is connected through the MPCA8.

12. Option RAM interface

12-1. Interface

The expanded RAM connector terminals are shown in the table.

The 72 pin S.O. DIMM is used for the connector.

Extension RAM connector terminals

Selector

/AS

CLK WAIT RESET Counter

START

/RESET

/EXWAIT

/VWAIT

/LCDWAIT

/WAITZ

WAIT

enable

For

RASP-

/RESET for 1,2,3WAIT

WAIT

enable

For

MISC

WAIT

Count

For

RASP

Selector

/RESET

for

1WAIT

/RESET

WAIT

Count

For

MISC

WAIT

Count

For

RASPN

WAIT

Count

For

RASPN

WAIT

enable

For

VRAM

•

VGA

I/O

Terminal autoweight signal

Fig. 10

TXD2(P87)

SCK2(P83)

RXD2(P84)

TXDI

SCKI

RXDI

H8/510

MPCA8

INT1

IRQ0

RES

STOP

(P57)

RESET

STH

HTS

SCK

CKDC9

KRQ

SHEN

STOP

HTS2

SCK2

STH2

HTS

SCK

STH

SRES

RESET

FTI2

CKDC9

HTS1

SCK1

STH1

HTS

SCK

STH

INT4

SHEN

RESET

reset from MAIN

VFDC

VFD

UP-P16DP/UP-I16DP

Key

Buzzer

Signal

Name

No.

GND 1

GND 2

—3

—4

—5

—6

—7

—8

—9

—10

A14 11

A15 12

A16 13

A17 14

A18 15

A19 16

—17

PCE22_E 18

PCE21_E 19

—20

PSREF 21

PCE22_O 22

PCE21_O 23

GND 24

Signal

Name

No.

—25

—26

—27

—28

A13 29

A12 30

A11 31

A10 32

A9 33

A8 34

A7 35

A6 36

A5 37

A4 38

A3 39

A2 40

A1 41

A0 42

D15 43

D14 44

D13 45

D12 46

D11 47

D10 48

Signal

Name

No.

D9 49

D8 50

D7 51

D6 52

D5 53

D4 54

D3 55

D2 56

D1 57

D0 58

GND 59

OWR 61

—62

—63

—64

—65

—66

HWR 67

—68

VMEM 69

VMEM 70

GND 71

GND 72

1 2 ... 46 47 48 49 50 51 52 53 54 55 56 ... 88 89

Comments to this Manuals

No comments

Sharp ER-A770 Service Manual Page 51

Comments to this Manuals

Related products and manuals for Cash registers Sharp ER-A770