PRINCIPLES OF OPERATION
(1)Main Logic Board
The main logic board’s CPU passes data transmitted from the host computer into the local RAM. It then reads the data from the RAM, arranges it in accordance with the ROM program, and prints the results by issuing appropriate drive signals to the printer mechanism.
[Block Descriptions]
a. CPU: HD6413002F16 CMOS
b.EPROM: 256K × 8 bits
Stores the CPU control program.
c.PSRAM: 128K × 8 bits Work area and data buffer.
d.EEPROM: 1024 bits
Stores printer settings. Settings can be changed by software. (Used in place of dip switches.)
e.Interface
Interfaces the main board with the host computer. Two versions available: RS232C and Centronics.
f.Gate array
Handles signal input, output, and conversions.
g.Drivers
The various drivers convert signals received from the CPU and gate array into drive signals that directly control the printer mechanism.
(2)Printer Mechanism
Comprised of thermal head, platen,
(3)Power Supply Unit
Converts primary power to DC5V, DC24V.
(4)Peripheral Unit
External device (such as cash drawer) driven by signals issued from the main logic board.
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