Pc Board; Microprocessor Chip - Mpu; Mpu Pin - Atari CX 5200 Field Service Manual

PC
Board
The
console you are servicing may
contain either the
original
PC
Board
Number
CA018087
or the
newer
PC
Boards
Numbers CA020108
or
CAQ21374.
See
Page
1-1 of
this
manual
for
an explanation
of
the three board's differences.
The
PC
Board
consists of:
•
28 Integrated Circuit Chips
on
PC
Board
Number CAQ18087;
26 Integrated
Circuit
Chips on
PC
Board
Number
CA020108;
24 Integrated Circuit Chips
on
PC
Board
Number CA021374.
•
a cartridge socket
•
an
RF
module
•
various discrete
components
The major
chips
on the
PC
Board
are:
Microprocessor Chip -
MPU
The
microprocessor
(MPU)
is
the
brain of the 5200.
It
makes
the major decisions
based on information from the
ROM
cartridge
and the
Random
Access
Memory.
Figure
1-3
shows the
pin
assignments
for the
MPU.
ROY
h
I5q
YNC
VCC
RES
39
h
38 SO
37
*0 UN)
36
B/W
33
O
HALT
3#
3
B/W
33
3
>
32
3
01
10
6502
31
02
30
03
12
29
3
0»
13
28
3
03
1»
27
3
06
13
26
3
07
23
3
A16
17
2*
3
A14
18
23
3
A13
19
22
3
A12
20
21
3
vss
Figure
1-3.
MPU
Pin Assignments
CX5200
Field Service
Manual
1-4