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Toshiba FS-160 SERIES User Manual

Page 43

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6. DISPLAY

An HMCS-45A is used for the display controller indentified by ICS.

Receiving the 4 bit parallel display data sent through connector

CN3, it displays the same contents (10 digits) on the FIU and BIU
and controls the buzzer.

After being input to the display controller, the display data from

the CPU is output from each port as the segment plate signals and

the grid signal for each digit. These signals are amplified by ICl

to ICG and then sent to the FIU and BIU in parallel. The buzzer

control signal is output from the D1 port and is driven by IC7 and

transistor Ql.

There are six types of power supplies to be delivered to the
display:

-5V, +5V, -VD, VFl, VF2, VM. They are sent from the

power supply unit through connector CN3. +5V and -5V are used as

power supplies for the ICs, -VD, VFl, and VF2 as power supplies for

the fluorescent display tube, and VM for driving the buzzer.

Table 6.1 lists the port functions of the printer controller.

Common to FIU and BIU

ICS

lOG

V

p

1 1

n

1 1

1

J

r

/

L

1 L

y

V

V

2G

IG

S(a)

S(g)

(

1

/

2

)

t)

(DP)

R20

R2*3

D1

D0

R30

INT0

R33

R40

R41

ROO
ROl
R02

D2

D3

/

/

i

\

KU J

1

ILMCS -45A

ACKito CPU)

CS

PA0
PAl
PA2

PA3

Fig. 6.1 Display Circuit Block Diagram

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