Epson ActionLaser 1600 Service Manual page 86

Principles of Operation
Table 2-2 lists the functions of the chief elements of the C125 MAIN board.
Table 2-2. Functions of the Major Components of the C125 MAIN Board
Location
C o m p o n e n t
ICI
MB86930 RISC
CPU
IC9
E05A91 ASIC
IC25
E05A92 ASIC
E05A93 ASIC IC24
IC21,22
Two 8M ROMs
or or
IC7, 8,
four 4M ROMs
18, 15
Two 8M ROMs IC4, 5
IC10
EEPROM
IC16, 17,
DRAM
19, 20
ADM232 IC28
IC8
MC34050
2-28
The CPU, which operates at 17.6 MHz, manages the
video controller operation.
This ASIC contains the following functions:
. Address decoding
. DRAM management (refresh control,
RAS/CAS control)
This ASIC contains the following functions:
. Video signal processing
. BiRITech
. EMGTech
This ASIC contains the following functions:
. Video interface
. Bi-parallel interface
. RS-232C interface
. RS-422 interface
. LocalTalk module control
. Type-B interface card control
. Control panel control
These ROMs are code ROMs.
These ROMs are font ROMs.
This EEPROM stores the following:
. Model type
. Printed page counter value
. Toner life counter value
. Jam counter value
. SelecType settings
These DRAMs are used as the CPU's working area:
input buffer, image buffer, etc.
This IC changes the RS-232C signal level.
This IC changes the RS-422 signal level.
EPSON ActionLaser 1600 Service Manual
Function