Main Control Circuit Operating Principles; Figure 2-20. Main Control Circuit Block Diagram - Epson Stylus 1500 Service Manual

Operating Principles

2.3.2 Main Control Circuit Operating Principles

The main control circuit for this printer is the C172 MAIN Board, which is controlled by a 16-bit
TMP96C061AF CPU (IC1) running at 24.57 MHz. A 4M DRAM (CAS method) on this board is controlled
by the CPU itself. The CPU manages the Type-B interface control.
Gate array E05B16 (IC2) manages the printhead driver control, external Centronics
panel, and control motors.
This board is also equipped with a 93C46 EEPROM (IC11) to store parameters such as the printer mechanism
control parameter, default setting parameters, and the special counter value used for printhead (ink
management) protection.
The NJU6355E timer IC (IC10) counts each time the printer is cleaned and keeps track of how long the
printer is not used, thereby allowing the printer to be cleaned only when necessary.
PROM(4M)
(IC3)
Type-B I/F
P S C
+42 VDC
+ 5 VDC
Sensor
From A
From B
From B

Figure 2-20. Main Control Circuit Block Diagram

2-16
PROM DRAM
(IC4) (IC17)
C P U
TMP95C061AF
(IC1)
C L K
SD I/O
+5 V
(IC10)
Lithium
Battery
NJ U63 5 5 E
(Timer
Counter)
Black / Color
Common Drive Circuit
Black/ Color Nozzle Selection
CR Motor
Driver Circuit (C15)
PF Motor
Driver Circuit (IC16)
Stylus 1500 Service Manual
DRAM CG-ROM CG-ROM
(IC7)
(IC18) (IC6)
Data Bus
Address Bus
PST592D
(IC9)
E05B16
Panel
(IC2)
EEPROM
(IC11)
93C46
(IC8)
M51955B
Carriage Unit
Black Head
SED 6100D0 A
(64 Nozzles)
(U1)
SED561 9D0 A
Color Head
(U1)
(Option)
CR Motor
PF Motor
®
parallel I/F, control
Reset IC
for Logic
Reset IC
for Power
Rev. A