Epson 4003353 - Manual (Page 45)

Sty/us Color Service Manual Operating Principles
2.3.2 Operating Principles of the Main Control Circuit
The main control circuit of this printer is the C137 MAIN board. This circuit is controlled by the
16-bit CPU (ICI), running at 14.7456 MHz. This CPU has a unique architecture capable of
handling data on the data bus at either an 8-bit or 16-bit bus width. Because of this, a 16-bit or 8-bit
data bus width-type ROM is used on this board, increasing the internal processing speed. Also, the
CPU has a unique architecture capable of the refresh control function. A 4M D-RAM
method) on this board is controlled by the CPU itself. The CPU controls the serial interface control
for Mac).
Gate array manages drive control, external parallel I/F,
extension CG board and the control panel, and the controls that create the 4-bit signal for the
carriage or the paper feed motor. (The carriage and paper feed motor are controlled by the current
duty data.)
This board is also equipped with to store certain parameters, such as the
printer mechanism control parameter, default setting parameters, as well as a special counter value
used for
(ink management) protection.
The timer IC counts each time the printer is cleaned and keeps track of how long
the printer is not used, thereby allowing the printer to be cleared only when necessary.
Reset
(Power)
L 1 1 I I 1 I
Type B l/F
I
(lCl)
Panel
DMAREQ
I I
Cl 37 MAIN Board
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
NJ U6355E
(Timer
Counter)
Carriage
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CD
From A Black/Color head ➤ Black 64 nozzle
Common driver Circuit (UI
32-pin socket only
From B ● Carriage/Paper feed
and European ver. only)
Motor Driver 8M is only equipped in NLSP ver.
Figure 2-18. Main Control Circuit Block Diagram
Reset
(Logic)
Rev. A
2-15