Control Circuit Operation; Control Circuit Operation Overview - Epson LQ-1170 Service Manual

2.3 CONTROL CIRCUIT OPERATION

The control circuit consists of three boards: the C060 MAIN board (the main control board), the C060
DRV board (the drive board), and the C060 PNL board (the control panel board). This section describes
how these boards work.

2.3.1 Control Circuit Operation Overview

The printer's CPU is an 8-bit CPU TMP90C041 that runs at 10 MHz.
the printer. The E05A49 gate array contains
memory and 1/0 areas. The PU 4135 rationalizes and simplifies the circuitry and holds all the driver
circuits for driving the printer mechanism on five chips.
diagram form.
1
1
1
r ----------------
1
1
1 Parallel
l / F
1
1
1
1
- - - - - - - - 1
Option
' l/F
1
1
!
, 1--- ---- - J
1
1
1
1
1 V r e f
Circuit
I
4.741 v
1
1
t
1
L - - - - - - - - - - -
~ ---------- - - - - - - - - - - - -
1
1
1
I
1
1
1
1
- - - - - -
- - - - - - - - - - - - -
- - -
Gate array
GA
Platen-gap sensor
GAP
Front paper-out detector (positioned in front of
SPE1
Release sensor
LEVER
Rear paper-out detector (positioned behind the
Home-position sensor
HOME
Carriage motor
CR motor
Paper advance motor
PF smotor
- - - - - - - - - - - - - - - -
GA
E05A50 (4D)
CPU TMP90C041 (2C)
- - - - - - - - - - - - - - - - - - - -
- - - - - - - - - - - - - - - - - - -
- - - - - - - - - - - - - - -
- - - - - - - - - - - - - - - - - - - - - -
- - - - - -
, 1
- - - - - - - - - - - - - - - - - -
P r i n t e r
2-17. Control Circuit Block Diagram
Figure
management functions that assign
various memory
Figure 2-17 shows the control circuits in block
- - - - - - - - - - - - - - - - - - -
- - - - - - - - - - - - - - - -
EEPROM
(4 c)
PROM
5 12K
( 1 E)
(6 E)
(5 E)
- - - - - - - - - - - - - - - - - - - - - - - - -
SLA7024M
PU4135 X6
(1C15)
.
- - - - - - - - - -
CR Motor
Printhead
- - - - - - - - - - - - - - - - - - - - - - - - - - - - -
- - - - - - - -
the printer mechanism)
printer mechanism)
It controls all the components of
- - - - -
- - - - - - - - - - - - - - - - - - - - - 1
CN1
--- ------ -
Pu 1501
- - - - - - - - - - - J
- - - - - - - - -
PF Motor
I
1
1
!
I
1
I
1
I
1
1
1
1
1
1
1
1
1
1
1
1
1
1
I
1
1
I
1
1
1
1
1