Epson U375 - TM B/W Dot-matrix Printer, Technical Manual

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2-16
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Memory map
The printer has one ROM area (64KB) and one RAM area
(32KB). The memory map is illustrated below.
CPU’s internal RAM
Unused
Gate array expansion ports, etc.
External RAM area (receive
buffer, print buffer, etc.)
Program area
Unused
Character generator area and
blank page data area
Figure 2-39. Memory Map
2.3.2 Principles of Operation
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Power supply circuitry
Figure 2-40 shows the power supply circuit for the printer.
The voltages supplied by this power supply circuit and their
uses are shown in Table 2-3.
The description of the power supply circuit is the same for
the TM-U375 and TM-U375P, but the diagram for the TM-
U375P is different from Figure 2-40. Refer to Chapter 7 for
the TM-U375P power supply circuit diagram.
Table 2-3. Power Supply Voltage Usage
00000H
00280H
00800H
01000H
08000H
10000H
80000H
88000H
Voltage
+5V
+24V
Usage
Logic circuit
Paper roll near-end sensor
Various sensors in the printer mechanism
Printer mechanism:
• Driving the stepping motor
• Driving the print head solenoid
• Driving various solenoids
Driving the drawer kick-out
Driving the customer display
CONFIDENTIAL