Video Controller Operation; C144Maln Board Operation; Figure 2-31. C144 Main Board Block Diagram - Epson ActionLaser 1300 EPL-3000 Service Manual

Operating Principks

2.2 VIDEO CONTROLLER OPERATION

The video controller section generates the video signals for the received data. 'l'he video controller
is a separate section of the C144 MAIN board.
2.2.1 C144 MAIN Board Operation
Figure 2-31 shows a block diagram of the video controller circuit section of the C144 MAIN bed.
The C144 MAIN board contains the video controller, which consists of a 16-bit 68000 (16.67 MHz)
CPU, the standard cells developed tbrthis printer, D~s, ROM, anda 16Kbit EEPROM.
ROM 16M
CPU
68000
Option l/F

Figure 2-31. C144 MAIN Board Block Diagram

Table 2-3 lists the functions of the C144 MAIN board elements.
Table 2-3. Functions of C144 MAIN Board Elements
Element Location
66000 CPU
IC1O, 11,23
DRAM
2-20
Option
ROM
DRAM
l/F
Parallel
CPU, which operates at 16.67 MHz, manages the video
The
controller
circuit ODeration.
This ASIC contains the folbwing functions:
. Interrupt control
Address decoding
.
Cbck control
DRAM management (refresh control, RAS/CAScontrol)
processing
Image
interface
Video
This ASIC contains the folbwing functions:
Parallel interface
DRAM management with the E05A83
This ASIC contains folbving functions:
Toner Save Mode function
This EEPROM stores the following:
Model type
Printed page counter value
. Toner life counter value
Printer settina
These DRAMs are used as the working area of the CPU:
Function
buffer. etc.
-
ADDRESS
DATA
CONTROL
Rev. A