CPU
The printer uses an external 8-bit and internal 16-bit CPU, with an external clock of 14.7 MHz.
The CPU (U5) controls the internal processing of the printer according to the printer control
program written in EPROM (U8).
CPU pin functions
Pin
No.
CPU
Function
Signal Name
I/O
Level
Description
1
P57
ELED/DSW9
I/O
TTL
ERROR LED. LOW: on. DIP SW 2-1 is read when
P100, P101 are LOW.
2
NMI
NMI
I
TTL
Not used (connected to +5 V directly).
3
P100
AC1/DSEL
O
TTL
Auto cutter drive (1) and DIP SW read selection.
LOW: read (read once after initialization).
HIGH: break status when used as motor control
port.
4
P101
AC
O
TTL
Auto cutter drive (2) and DIP SW read selection.
LOW: read (read once after initialization).
HIGH: break status when used as motor control
port. This pin must change at the same time as
P100.
5
AVCC
AVCC
I
(+5 V)
Analog/digital converter standard voltage.
6
AVSS
AVSS
I
(0 V)
Analog/digital converter GND terminal.
7
P60/AN0
V DTC
I
Analog
+24 V power voltage detection.
8
P61/AN1
HD TEMP
I
Analog
Head temperature detection.
9
P62
NE
I
TTL
Paper roll near-end detection.
LOW: no paper; HIGH: paper present.
10
P63
DK S
I
TTL
Drawer open/closed. LOW: open.
11
P64
RE
I
TTL
Paper roll end detection.
LOW: paper present; HIGH: no paper.
12
P65
HP DTC
I
TTL
Carriage home position sensor.
LOW: home position.
13
P66
DET
I
TTL
Host interface DET.
14
P67
AC RST
I
TTL
Auto cutter position detection (reset).
15
VCC
VCC
I
(+5 V)
Main power terminal.
16
P70
CTS
I
TTL
Host interface CTS. LOW: on.
17
P71
CCE
O
TTL
4M ROM CE signal. LOW: active.
18
P72/RXD1
RD
I
TTL
Host interface RD. LOW: on.
19
P73/CLK1
CLK IN/DTR
I/O
TTL
Host interface CLK IN/DTR.
20
P74/TXD1
SD
O
TTL
Host interface SD. LOW: on.
21
RESET
RESET
I
---
CPU reset input. LOW: on.
22
CLK
CLK
O
TTL
Not used. Open.
23
VSS
VSS
I
(0 V)
GND terminal.
2/DSEL
— 43 —
Summary of Contents for UP-250
Page 1: ...EXTERNAL PRINTER FEB 2000 MODEL UP 250 without price TECHNICAL MANUAL ...
Page 95: ... 86 END END Yes No Action 4 Replace main PCB Replace printer OK Action 4 mechanism assembly ...
Page 136: ... 127 ...
Page 149: ... 140 Main Circuit Board Parts Layout ...
Page 150: ... 141 RS 232 Serial Interface Circuit Board Parts Layout ...
Page 151: ... 142 IEEE 1284 Parallel Interface Circuit Board Parts Layout ...
Page 152: ...RS 485 Serial Interface Circuit Board Parts Layout 143 ...
Page 160: ... 151 Case Unit Lubrication Points Diagram 4 G 31 4 G 31 3 G 31 3 G 31 ...
Page 163: ... 154 EXPLODED DIAGRAM FOR TM U200B U210B NO 1 ...
Page 164: ... 155 EXPLODED DIAGRAM FOR TM U200B U200PB U210B U210PB NO 2 ...