2-20
ROM (64KB)
The printer control program and the character generator
data are written in ROM (U15). The control program
controls the basic operations of the printer; all CPU (U12)
operations follow this program.
RAM (32KB)
RAM (U16) is used as temporary storage for the following:
• Data received from the interface (receive buffer).
• Pattern data to be printed by the print head (print buffer).
• Data used by the CPU (U12) during processing (flags,
pointers, etc.).
Gate array
The gate array (U19) has five 8-bit I/O ports which can be
used by the CPU (U12) as I/O ports allocated in the memory
map (expansion port function).
When the ALE signal is high, the gate array latches the
multiplexed address signals/data signals output by the
CPU (U12) and samples the address signals (address latch
function).
The functions of each of the terminals on the gate array are
described in Table 2-5.
Table 2-5. Gate Array Pin Assignments
No. Pin
Signal
I/O
Function
Name Name
Print solenoid #8 drive signal Low: on
Print solenoid #7 drive signal Low: on
Print solenoid #6 drive signal Low: on
Print solenoid #5 drive signal Low: on
Print solenoid #4 drive signal Low: on
Print solenoid #3 drive signal Low: on
Print solenoid #2 drive signal Low: on
Print solenoid #1 drive signal Low: on
DIP switch setting SW-1
DIP switch setting SW-2
DIP switch setting SW-3
DIP switch setting SW-4
DIP switch setting SW-5
DIP switch setting SW-6
DIP switch setting SW-7
DIP switch setting SW-8
Print solenoid #9 drive signal Low: on
Print solenoid drive trigger
Low pulse: trigger
Unused; open
Error LED Low: on
DIP switch selection; read: PB0 to 7
High: DIP switch 1 selected
Low: DIP switch 2 selected
Platen switching magnet hold
High: hold
JOURNAL OUT LED Low: on
VALIDATION/SLIP LED Low: on
Unused; connect to GND
Unused; connect to GND
Unused; connect to GND
Unused; connect to GND
Unused; connect to GND
Unused; connect to GND
Unused; connect to GND
Unused; connect to GND
Paper roll near-end sensor
Low: paper available
High: paper near end
Host I/F DR Low: on
IM I/F DR Low: on
Paper load detection Low: active
Paper feed switch Low: active
Release switch Low: active
Cover open/closed detection
High: open
Low: closed
IM connection
High: not connected Low: connected
2
3
4
6
7
8
9
10
12
13
14
15
16
17
18
19
20
21
22
23
24
25
5
45
26
27
31
32
33
34
35
36
37
38
39
40
41
42
43
44
PA0
PA1
PA2
PA3
PA4
PA5
PA6
PA7
PB0
PB1
PB2
PB3
PB4
PB5
PB6
PB7
PC0
PC1
PC2
PC3
PC4
PC5
PC6
PC7
PD0
PD1
PD2
PD3
PD4
PD5
PD6
PD7
PE0
PE1
PE2
PE3
PE4
PE5
PE6
PE7
HEAD8
HEAD7
HEAD6
HEAD5
HEAD4
HEAD3
HEAD2
HEAD1
DSW1
DSW2
DSW3
DSW4
DSW5
DSW6
DSW7
DSW8
HEAD9
HD_COM
—
ER_LED
SW_CHG
PL_HG
JO_LED
PPR_LED
—
—
—
—
—
—
—
—
NE
DSR
IM_DSR
PL_SW
PF_SW
RL_SW
F_COVER
IM_DET
O
I
O
O
O
O
O
O
O
O
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
See Chapter 7 for the TM-U375P gate array pin assign-
ments.
CONFIDENTIAL
Summary of Contents for U375 - TM B/W Dot-matrix Printer
Page 2: ...Technical manual TM U375 U375P English 4005791 Copied Date 199 Copied by ...
Page 54: ...2 23 Figure 2 44 Host Interface Circuit and Custor Display Interface Circuit CONFIDENTIAL ...
Page 58: ...2 27 Figure 2 49 Carriage Motor Drive Signal Timing Chart CONFIDENTIAL ...
Page 149: ...6 2 Circuit 1 CONFIDENTIAL ...
Page 150: ...6 3 Circuit 2 CONFIDENTIAL ...
Page 151: ...6 4 Circuit 3 CONFIDENTIAL ...
Page 152: ...6 5 Circuit 4 CONFIDENTIAL ...
Page 153: ...6 6 Circuit 5 CONFIDENTIAL ...
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Page 168: ...7 9 Table 7 5 TM U375P Gate Array Pin Assignment continued CONFIDENTIAL ...
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