Epson DFX-8500 Service Manual page 72

Table 2-5 describes the functions of the main components of the C204 main and C204 DRV boards.
Board IC Name
C204 Main TMP95C061
(CPU)
E05B36
(Gate Array)
PROM
RAM
EEPROM
ADM232
PST591D
C204 DRV STK681-050
STK67138MK4
uPC393C
Table 2-5. Main IC Functions
Location Functions
IC2 Receives data from the host computer via the gate array,
loads the data to the input buffer in the RAM, and converts
the image data to print data.


IC1 /CS (Chip Select) signal creation


Address decoding


Address latching


Clock pulse creation


Printhead driver control


Carriage motor driver control


Encoder pulse I/O


Platen gap and head fan motor phase signal creation


Interface control


Abnormal current detection for the carriage and paper
feed motors


/RESET signal creation


PSB/PSE board control


LED control


DIP switch reading
IC5 Contains the program that runs the CPU.
IC14 Holds the CPU working area and buffers (input, line, and
image buffers).
IC11 Remembers printer settings while the power is off.
IC9 EIA to logic level voltage level converter
IC13 System reset IC
IC1 Drives the carriage motor.
IC2 Drives the paper feed motor.
IC3 Detects current in the carriage motor driver and feeds it back
to the gate array on the main board.
OPERATING PRINCIPLES
2-19