Service manual

2-20 Mechanism Configuration and Operating Principles Rev. B
Confidential
ROM or flash memory
The printer control program and the character generator data are written in ROM (U8) or in
flash memory (U101). The control program controls the basic operations of the printer. All CPU
(U5) operations follow this program.
56 P90 PF A/DSW5 I/O TTL Paper feed motor driver control 2-2 phase
excitation. All terminals on (LOW): hold.
DIP SW 1-5 to 1-8 read when P100, P101 are
LOW.
57 P91 PF B/DSW6
58 P92 PF C/DSW7
59 P93 PF D/DSW8
60 RD RD O TTL External memory data read signal.
61 WR
WR O TTL External memory data write signal.
62 P32 DKD1
O TTL Drawer kick-out driver signal 1. LOW: active.
63 P33 DKD2
O TTL Drawer kick-out driver signal 2. LOW: active.
64 P40 HEAD8
O TTL Print head #8 driver signal. LOW: on.
65 P41 HEAD7
O TTL Print head #7 driver signal. LOW: on.
66 P42 HEAD6
O TTL Print head #6 driver signal. LOW: on.
67 P43 HEAD5
O TTL Print head #5 driver signal. LOW: on.
68 P44 HEAD4
O TTL Print head #4 driver signal. LOW: on.
69 P45 HEAD3
O TTL Print head #3 driver signal. LOW: on.
70 P46 HEAD2
O TTL Print head #2 driver signal. LOW: on.
71 P47 HEAD1
O TTL Print head #1 driver signal. LOW: on.
72 P48 HEAD9
O TTL Print head #9 driver signal. LOW: on.
73 P51/T04 +24VCOM SW
O TTL Head, auto cutter, drawer kick-out power
switch. LOW: drive.
74 P52 CRCOM SW
O TTL Carriage motor power switch. LOW: motor
drive.
75 VCC VCC I (+5 V) Main power terminal (+5 V).
76 P53 PFCOM SW
O TTL Paper feed motor power switch LOW: motor
drive.
77 P54 CLK REQ O TTL HOST interface CLK REQ.
78 VSS VSS I (0 V) GND terminal.
79 P55 RTS
O TTL Host interface RTS. LOW: on.
80 P56 PLED/DSW0
I/O TTL PAPER OUT LED. Low: on.
DIP SW 2-2 read when P100 is LOW.
CPU pin functions
Pin
No.
CPU
Function Signal Name I/O Level Description