Epson TM U200D - B/W Dot-matrix Printer Technical Manual page 55

The figure below illustrates the circuit block diagram for the printer.
Print head
2-14 Mechanism Configuration and Operating Principles
AC adapter
DKD
ior PS |150 j
CN1 CN2
Main circuit board
CN7
CN11 CN8
Near-end
Various sensors
detector (optional)
Figure 2-16 Circuit board block diagram
I/F circuit board
CN1
CN2
CN4
CN5
CN9 CN6
(Not used) Paper feed motor
Host interface
Carriage motor
Rev.B