Sharp MZ-80B Service Manual

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The system diagram of the MZ-80B is shown in Fig. 4. With the CPU and its bus lines in the center, the memorie~
(main memory, boot ROM, V-RAMI, keyboard, cassette recorder, CRT display, clock, reset circuit, and I/O port are
arranged, showing the
relations with PlO, 8225, 8253, to constitute the MZ-80B.
RESET
SWITCH
'IPL
RESET
SWITCH
FRAME
GROUND
-11-
AC
I
n
POWER SWITCH
~
1
1
POWER UNIT
POWER
TC!ITv
ONIPL
-5V
RESET
GROUND
C
R
E
L-.
S
0
E
T
A
Z80A
CPU
"
4>
CRYSTAL
16 £
4MHz
OSCILLA-
MHZ'l TOR
31.25kHz
Jl
L
E
D
'IPL RESET " .. " Initial Program Loader RESET
-5-
Main Memol)'
RAM
32k bytes
IPL
ROM 2k bytes
".
RAM
32k bytes
ADDRESS
SELECTOR
" r
I
-,
I1
m
ADDRESS BUS
1 11 1
u:
11
IL
J I
J ~
T LB S
r-
HAN
Z80A-PIO
POK
4>
~
I
KEYBOARD
r--
Fig. 4 r

Sharp MZ-80B Specifications

General

Brand	Sharp
Model	MZ-80B
Category	Desktop
Language	English