NEC PC-8201 User manual

Per/oncll Computer
I Service Manual I
NEC NEC Corporation

0 1983 NEC Corporation
Tokyo, Japan
All rights reserved. No part of this publication may be reproduced in whole or in part
without
the prior written permission of NEC Corporation.

CONTENTS
i
CHAPTER 1 IKTRODUCTION
.....................
1.1 Specifications 1 . 1
................
1.2 Switches and Contrast VR 1-3
CHAPTER
2 EXTERNAL VIEW
CHAPTER 3 FUNCTIONAL SPEClFICATIONS
..................
3.1 Logical Specifications 3-1
........................
3.1.1 CPU 3-1
........................
3.1.2 ROM 3-1
........................
3.1.3 Rkil 3-1
....................
3.1.4 LCD Interface 3-3
...................
3.1.5 Printer Interface 3-7
................
3.1.6 Calendar Clock Interface 3-8
..................
3.1.7 Keyboard Interface 3-9
....................
3.1.8 Serial Interface 3-10
...................
3.1.9 Cassette Interface 3-13
................
3.1.10 Bar Code Reader Interface 3-13
..................
3.1.1 1 Interrupt Functions 3-14
.....................
3.1.12 110 Address 3-15
..................
3.2 Physical Specifications 3-21
.....................
3.2.1 Signal Lines 3-21
....................
3.2.2 Power Supply 3-29
...................
3.2.3 Structure and Size 3-30
................
3.3 Interface to Other Hardware 3-30
...................
3.4 Software Interface 3-30
....................
3.5 Human Interface 3-30
..........
3.6 Performance Specification for the PC-8201 3-33
.....................
3.7 Accessories -3-33
CHAPTER 4 DISASSEMBLY/REASSEMBLY
......................
4.1 Disassembly 4-1
....................
4.1.1 PC-8201 Cover 4-1
.....................
4.1.2 LCD Board 4-2
......................
4.1.3 Keyboard 4-2
..................
4.1.4 Power Supply Board 4-2
.....................
4.1.5 Main Board 4-3
4.2 Reassembly
...................... 4-3
.....................
4.2.1 LCD Board 4-3
......................
4.2.2 Keyboard 4-4
...................
4.2.3 Keyboardswitch 4-4
..................
4.2.4 Power Supply Board 4-5
.....................
4.2.5 Main Board 4-5

........................
4.2.6 Rob1 4-5
......................
1.3 Installation - 4-6
.............
4.3.1 Inserting Cartridge (RAM. ROhl) 4-6
............. .....
4.3.2 Battery Installation 4-7
4
CHAPTER 5 OPERATION TEST
...............
5.1 Operatiorls Test Flow Chart
.................
5.2 CPU Peripheral Circuit
..........
5.2.1 PC-820
1 Power Supply Operation Test
.................
5.2.2 Reset Operation Test
..............
5.2.3 CPU (80C85) Operation Test
...............
5.2.4 CPU Clock Operation Test
.............
5.2.5 Calendar Clock Operation Test
.................
5.3 110 Peripheral Circuit
.................
5.3.1 LCD Operation Test
...............
5.3.7 SI02 I'ort Operation Test
.............
5.3.3 BCR Interface Operation Test
............
5.3.4 RS-733C Interface Operation Test
.............
5.3.5 SIO l Interface Operation Test
.............
5.3.6 Printer Interface Operation Test
5.3.7 Audio Cassette Interface Operation Test
..........
................
5.3.8 110 Port Operation Test
................
5.3.9 Speaker Operation Test
...............
5.3.10 Keyboard Operation 'Test
CI-IAPTER 6 TROUBLESHOOTING
...............
6.1 Troubleshooting Flowchart
.................
6.2 CPU Peripheral Circuit
............
6.2.1 PC-830 1 Abnormal Power Supply
...............
6.3.2 PC-8201 Abnormal Reset
............
6.2.3 PC-820 1 Abnormal CPU (80C85)
6.2.4 Abnornial CPU Clock .................
............... 6.2.5 Abnorn~alCalendar Clock
.................
6.3 110 Peripheral Circuit
................ 6.3.1 Abnormal LCD Display
6.3.2 Abnorrnal S107 Port
.................
6.3.3 Abnormal BCR Interface ...............
6.3.4 Abnormal RS-232C Interface ..............
............... 6.3.5 Abnormal SIO1 Interface
6.3.6 Abnormal Printer Interface
...............
6.3.7 Abnormal Audio Cassette Interface ............
................. 6.3.8 Abnormal I/O Port
6.3.9 Abnormal Speaker
..................
.................
. 6.3.10 Abnormal Keyboard
-b
APPENDIX A OPERATIONAL hIISTAKES

APPENDIX B IC REMOVAL
................
B- 1 Necessary Equipment - APX-B-I
.............
R-2 ICs on Printed Circuit Board APX-B- I
.................
B-3 ICs with Sockets .APX-B-2
.......
B4 Drawings of Insertion and Removal of IC .APX-B-2'
APPENDIX C PARTS LIST
APPENDIX
D CIRCUlT DlAGRAM
APPENDIX E LSI DATA SI-IEET
-iii-I(-iv- blank)

1 .I Specifications
(1) Main Components
a) Keyboard
67 keys
Function keys:
Cursor lead keys:
Others:
CHAPTER 1
INTRODUCTION
b) LCD
Effective display area:
Display panel:
Dot size:
Dot pitch:
Display characters:
Reverse:
19
1.2(W) x 50.4(H) mm
240
x 64 full dot matrix
0.73
x 0.73 nlm
0.8 rnm
40 (characters) x 8 (rows)
By escape sequence
c) Operation Batteries
Batteries:
Operation time:
Four type
A.4
Alkaline-manganese batteries
4.5 days
(At four l~ours/day)
18 days
(At one hour/day)
Note: With 110 disconnected
Battery cassette: 70(W)
x 80.5(D) x 19(H)mm
Power OFF: Man~~alpower off
(It is possible to command in BASIC.)
(Variable minutes - one to twenty-five min-
utes)
Low voltage display: Light a LED
(Operate for more than twenty minutes after
lighting the LED.)
d)
Memary Protection Battery (On main P.C.B)
Battery: Rechargeable battery
Protection time: About 26 days
( 1 GI< bytes)
About 7 days (14K bytes)
Recharge method: Trickle charge by AC adapter or operation
batteries

e) LSIs
CPU:
CLOCK:
f) Dimensions:
(2) 110 interface
a) RS-232C
Itfordlength:
Parity:
Stop bit length:
Baud rate:
b) S102
Distance of transfer:
Word length:
Baud rate:
Parity:
Stop bit:
c) SIO1
Distance of transfer:
Word length:
Baud rate:
Parity:
Stop bit:
d) CMT
Distance of transfer:
Baud rate:
File format:
Output level:
e) Printer:
80C85
Code and pin compatible with3085
Standard 32K bytes
Option 32K bytes (connect a 1C socket)
Standard 16K bytes
Option 16K bytes (connect a IC socket)
Option 32K bytes (connect a IC socket)
Option 32K bytes (connect a RAM cartridge)
2.4
MHz
Front;
300!W) x 215(D) x 35(11) mm
Back:
300(W) x 215(D) x 6 l(1.I) mm
6.7 or
8 bits
Non, EVEN or ODD
1 or 2 bit
75, 110, 300. 600, 1200, 2400, 4800. 9600.
19200 BPS
3 mMin.
8 bit
19200
Non
1 or 2 bit
3
mMin.
8 bits
19200
Non
1 or 2 bit
1.5 mhlin.
1200 or 600 (switchable by software control)
Compatible with N-BASIC
(binary file only)
hlIC level
Confornls to Centronics Standards.

f) BCR
g) Systeni slot:
(3) Special functions:
For connecting a lZAlCI cartrTdge.
.
A~~tornaticpower OFF
When 1.here is no program operation (awaiting
command) for ten minutes, the power is
automatically switched off.
1.2 Switches and Contrast VR
(1) POWER Switch
Move this switch towards the rear to turn the power ON. To conserve the
batteries, the PC-8201 automatically turns the power off if you do not use it for
10 minutes.
When an automatic power-off occurs, the switch will still be in the ON position even
though the power is OFF.
To turn the power ON. move the switch to the OFF position, then back ON.
(3) BACK UP I'OLb'EII Switch
This switch is for preventing discharge of the Ni-Cd battery for
RAhl back-up.
The I'C-8301A
will not operate regardless of the setting of the power switch unless
this switch
is ON. Set this switch to OFF position if the PC-8201 is not to be
used for a long timc.
Nole that the RAkl will not be backed up when this switch is set to llle OFF
position.
(3) RESET Switch
If the PC-8201 "locks-up" (the display will "freeze" and all keys seem to be
inoperative), press this button to return to the hlain Menu (start-up) screen. It's
highly unlikely that the PC-8201
will lock-up when you are using the built-in
Application Programs.
However, this situation may occur with customized programs.
(4) PROTECT Switch
This switch is for protecting the contents of 2nd
RAM. (BANK #2)
(5) DISPLAY ADJUSTMENT DIAL
This control is for adjusting the contrast of the LCD display relative to the viewing
angle.
1-3/(1-4 blank)

CHAPTER 2
EXTERNAL VIEW
Contrast mntrol
Power mLtch 1
Front
Back
Left Side
2- 1 /(2-2 blank)
Rear View

CHAPTER 3
FUNCTIONAL SPECIFICATIONS
3.1 Logical Specifications
3.1.1 CPU
(1) Available CPU
A 80C85 is used at
2.4 MHz.
(2) How to Reset
There are two kinds of reset: power on reset and mani~alreset. Pushing the reset
switch initiates
a warm-start: pushing it while pushing a shift-key and a control-key.
initiates a cold-start.
3.1.2 ROM
(1) Available ROX1
Available KOXI is ChlOS ROM, and the capacity is 37,K byte. (#0)
(2) User ROM
A user ROM is 32K byte. The user Rob1 area is equipped with an IC socket which
can be equipped with CbIOS Kohl. (#I)
3.1.3 RAM
( 1) Available RAM
Thc eight 2li-byte CMOS 1Cs arc used as RAM.
The system comes with l6K bytes
(STDRAM ).
(2) Optional RAhl
The PC-8201 is equipped with IC sockets for twenty-four 3K-byte CMOS ICs.
48K bytes. The first 16K bytes of this area are combined with the standard
16K byte
RAM to make a 32K byte RAhI area. The remaining 32K bytes, become
RAhl #2. There is also a 32K-byte RAM cassette ($3) port for external
memory. It call be connected with a system bus oulput in PC.
1 1 -M q;lRAM CASSETTE
Wr~te protect
0000 5witrh
lo~:ionl loptlonl loptfion)
Memory Configuration

Optional RAM #2 and RAM cassette 83 have write protect switches. and they can
select the address
(0 lo 7FFF or 8000 to FFFF) by software control.
-
Mernory is controlled at the following 110 port.
OUT A1 H
LADR 2
HADR
HADR 2
LADR 1
HADR
2121
HADR 1
SELECT ADDRESS (OH to 7FFFH)
LADR
BANK 90(ROM #0)
BANK
#1 (ROM #I)
BANK $2 (RAM #2)
BANK $3 (RAM if3)
LADR
SELECT ADDRESS (8000H to FFFFH)
STANDARD ROM
NOT USED
BANK #2 (RAM #2)
BANK
#3 (RAM $2)

3.1.4 LCD Interface
( 1) Available driver
HD44 102B (Ten) ............ Segment driver
Display
RAM 200 byte
HD44103B (Two) ............ Common driver
(2) Available LCD
LR-202C Number of dots
240 x 64
(3) Function of display
* 1 * Number of display characters
40 characters x 8 rows
(Display duty is 1132s.)
*2* Configuration of character
Both alphanumeric characters and graphic charactors can be displayed.
*3* LCD
I/O address. I/O port
Writing the command to LCD
Reading the status from LCD
* Display On/Off
The LCD is divided into the following IC blocks. Each block can be
displayed separately.
I
I
240 dots
OUT FO
DISP DISPLAY

The following OUT command selects which block is displayed on or off as Port A
and Port
B of 81C55.
-
OUT 09
OUT BA
B 1 corresponds to I'AO. and B2 corresponds to PAI. etc. B10 corresponds to
PB 1. A1 in each I/O port selects the corresponding LCD block, and is deselected
by a 0.
* Address Set
OUT FO
Bit 7 Bit 6
0 0 PAGE 0
0 1 PAGE 1
1
0 PAGE 2
1 1 PAGE 3
BIT 5 TO BIT 0 0 to 49 displayed by binary number

LCD each Block
8 bits
8
8
8
L
Set the RAM address in address counter at 110 port (Bit 7 to Bit 0).
PAGE 0
- - - - - -- - -
PAGE 1
- - - - - - - - - -
PAGE 2
------- ---
PAGE 3
* Set of starting page
OUT FO
Bit 7 Bit 6 Order of displayed page
(One-thityseconds duty)
0 0
0, 1, 2. 3
0 1
1, 2: 3, 0
1 0 ?,3. 1, 0
1 1
3, 0. 1. 2
*
Select address counter count up or count down
OUT FO
0
0011101
DOWN
UP/DO\irN SELECT THE ADDRESS COUNTER
0 Down counter
1 Up counter

This address counter is a loop counter whose rnax is fifty count. Aftcr displaying
the data, this countcr automatically counts up or count down.
-
* Read status
BIT 4
STATE OF RST PIN
BUSY
0 Normal
1 RST is low level. BUSY in Bit 7 is 1.
BIT 5 DISPLAY ONIOFF
0 Display Off
1 Display On
RESET
"9
DOWN
13 I'T 6 TYPE OF ADDRESS COUNTER
O> OFF
Down counter
Up counter
BIT 7 OPERATE THE COMMAND
0 Nor~nal
1
Operate IN F 1. OUT FO. and OUT F 1
command
*
Write or Read Display Data
BIT 7- 131T 0
Displayed data
This operates access with the
RAM whose address has already been selected. After
then, the address counter is counted up or counted down.

3.1.5 Printer Interface
The printer interface is an &bit parallel interface (Centronics compatible). The following
shows the printer interface port. Data is transmitted to Port
A at 81~55-andcontrol signal
from printer is transmitted to Port
C.
*
* Data transfer to printer
OUT 69
BIT 7 - BIT 0
Printer data port
765432 10
*
BUSY. SLCT signal from printer
PD7
SLCT
I
BUSY
0
1
PD6
BUSY
* Strobe printer
PDZ
SLCT
Deselect
Select
PD5
I
Printer READY
Printer BUSY
PDI
OUT 90
PDO
PD4
5
PSTB
PD3
PSTB STROBE PRINTER
0 Strobe Off
1 Strobe On

3.1.6 Calendar Clock Interface
Calendar clock interface is equipped with
an LSI for watch (pPD 1990AC).
The following
-
shows the 110 port.
* Command data output port
OUT 09
C2. C1. CO Conlnland output port
COO
CCK SHIFT CLOCK
0 Clock Off
1 Clock On
CDO Data output port
CCK
The first value is 05H
*
Command Strobe to the Clock
C2
OUT 90
TSTB
C1
TSTB COMMAND STROBE TO CLOCK
0 Strobe Off
1 Strobe On
CO
* Data from Clock
CDI
CLOCK DATA INPUT PORT
3 -8

3.1.7 Keyboard Interface
The keyboard is sensed by a software scan.
It transmits low signals (OUT -
B9. OUT BA)
to Port A or Port B at 81C55, and senses the depressed key by IN E8.
* Keyboard Interface Port
I
1011 1 1001 OUT B9
I
OUT BA
PA7- PA0
00000001
00000010
00000100
00001000
00010000
00100000
01000000
10000000
PB7 -PBO
00000001 CAPS --SHIFT
Key
L-z
K-A
I -Q
A/ - 0
8( - 1'
PAST , 9.)
INS
- DEL
BS
STOP --- I

3.1.8 Serial Interface
The serial interface uses an RS-232C. S101. or S102. switching them one another, by
USART IM6402.
-
* Interface Switching
OUT 90
SEL A SEL B
0 0 NOT USED
0 1
S102
1 0 SIO 1
1 1 RS-232C
7 6
*
Load to USART and control register
SEL A
OUT D8
SEL B
CLS2 CLSl PI EPE SBS
SBS
0
1
EPE
0
1
CLS 2 CLS 1
0 0
0 1
1 0
I 1
STOP BIT SELECT
Stop bit length
1 bit
If the length
of data is 5 bits, it is 5 bits.
In other cases, it is 1.5 bits
ODD PARITYIEVEN PARITY
Odd parity
Even parity
DISPLAY PARITY
Parity generation check
Disable parity generation check
DATA LENGTH
5 bits
6 bits
7 bits
8 bits

* USART 110 data
* USART Status Read
7 6543 2 1 0
-
TBRE PE FE OE
m/RD DATA CARRIER DETECT/IIING DETECT
0 On
1 Off
D7
OVERRUN ERROR
Generate an overrun error
D7 -- DO
USART DATA PORT
06
D5
F E FRAMING ERROR
1 Generate a framing error
PE PARITY ERROR
1 Generate a parity error
TBLE
1
D4
TRANShlITTER BUFFER REGISTER EhIPTY
Able to transmit data
D2
D3
LPS LOW POWER SIGNAL
I Dropped Power Voltage
Dl DO