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

REV.-A
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.
It controls all the components of
the printer. The
E05A49 gate array contains
various memory management functions that assign
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.
Figure 2-17 shows the control circuits in block
diagram form.
C060 PNL Board
~ --------,
1
1
t
1
1-- - -- - -- -1
C060 MAIN Board
r ----------------
-------------------
-----
-----
------
-----
----------------
I
1
1
1
I
I
1
GA
!
1
Parallel
EEPROM
E05A50 (4D)
(4 c)
I
I
I
1
l/F
1
1
I
I
..’
I
1
1
1
I
9
1
1
; ~ --------1
[ I Option 1
I
1
‘ l/F ‘-
;:J~M
;;;AM
MROM
;1
PROM
MROM
:
1
1
;1
5 12K
!
(5 E)
(6 E)
( 1 E)
~~E )
~~E ) :
, 1--- ---- - J
1
1
I
I
1
I
1
I
I
1
1
1
9
1
1
I
I
1
1
1
Vref
CPU TMP90C041 (2C)
I
I
1
Circuit
1
I
4.741 v
t
1
1
1
1
t
1
1
L ---------- -
----- ----------------1
------
-------
------
-----
--------------
-
C060DRV Board
CN1
--- ------ -
1
-------------
-
-----
------
---------------
~ ----------
- -
-----
-----
I
1
1
1
I
1
I
1
I
I
1
I
I
1
I
I
PU4135 X6
SLA7024M
Pu 1501
1
1
1
I
(IC8-I 3)
(1C15)
(IC20)
.
I
1
1
1
i i
-----
------
J
-----
----- ----
-----
1------ -- --- - ------
------
-----
------
-----
, 1
;,,,,,--------,-----------,---------,-----------[
: HOME PE 1 PE2 GAP LEVER
Printhead
1
8-- - --- --
------
-----
------
------
------
--------
Printer Mechanism
CR Motor
PF Motor
1
I
1
------
------
-----------------
GA
GAP
SPE1
LEVER
PE2
HOME
CR motor
PF smotor
Gate array
Platen-gap sensor
Front paper-out detector (positioned in front of
Release sensor
Rear paper-out detector (positioned behind the
Home-position sensor
Carriage motor
Paper advance motor
Figure
the printer mechanism)
printer mechanism)
2-17. Control Circuit Block Diagram
2-14