Epson FX-2170 Service Manual page 72

FX-2170 Service Manual
The following figure shows the data flow from the host computer to the printhead. Data sent from the host
computer is converted to image data and transmitted to the printhead through the gate array.
Option I/F
Parallel I/F
Host
Computer
The following table lists the each function of the main components of the C166 MAIN board.
IC Location
CPU IC1
Gate Array IC2
EEPROM IC 8
ROM IC 3
RAM IC 5
SLA7024M IC 12
UDN2917EB IC 11
Rev.A
Gate Array
E05B13
Data latch
and
data output
Printhead drive
circuite
Figure 2-31 Data Flow
Table 2-7 Functions of the Main Board
Receives data from the host computer and sends it to the input buffer
in RAM (under interrupt processing control). Extends the input data
held in the buffer to create image data. Loads this image data to the
image buffer in RAM. Transfers the image data to the printhead
drive circuit.
Controls the functions below:
Controls output data from the internal block
Memory management
Address latch of the address/data bus from the CPU
Clock control unit
Bit manipulation
Interface control
Expanded parallel port
Printhead control
Motor control
An electrically writable and erasable ROM used to hold such
information as the TOF position and bidirectional adjustment value.
The ROM contains the program that runs the CPU and holds the
character design (also called the character generator).
The RAM contains the CPU working area and the buffers
Drive circuit for the CR motor
Drive circuit for the PF motor
Operating Principles
CPU
TMP96C041AF
Print data
conversion 1
Print data
conversion 2
Image data
transfer
Function
RAM
Input
Buffer
Line Edit
Buffer
Image
Buffer
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