Roma Board (Main Board); Figure 1-16. Roma Board - Epson LQ-2550 Technical Manual

REV.-A

1.8.2 ROMA Board (Main Board)

Figure 1-16 shows the ROMA board, which contains an HD64 180R1 P6 (main) CPU andaPPD7810HG
(sub) CPU to control the operation of the printer. Driver circuits for the motors, solenoids, printhead,
and sensors are also included on this board. The main ICS on the ROMA board are:
CPU
HD64180R1 P6 (1 3A) . . . . . . . . . . .
pPD7810HG (7B) . . . . . . . . . . . . . . . . . .
Gate Array
EO5A1OAA (1 4A) . . . . . . . . . . . . . . . . . . .
E05A02LA (2A) . . . . . . . . . . . . . . . . . . . . . .
Memory IC
MASK-ROM (1 2A) . . . . . . . . . . . . . . . . . .
PS-RAM (9A) . . . . . . . . . . . . . . . . . . . . . . . . . . .
ST-RAM* (1OA) . . . . . . . . . . . . . . . . . . . . . . .
Universal IC
M546 10P (1 1 B) . . . . . . . . . . . . . . . . . . . . .
STK6981 H (7D) . . . . . . . . . . . . . . . . . . . . .
STK66082E (1A) . . . . . . . . . . . . . . . . . . .
)
8-bit one-chip CPU (main control)
8-bit one-chip CPU (sub control)
Memory management unit (MMU) IC
Carriage (CR) and paper feed (PF) motors phase pulse control unit
Platen gap (PG) and color select (CS) motors phase pulse control unit
Main CPU program, 256 K-bit
Sub CPU program, 256 K-bit
Character generator, 2M-bit
Buffers, working area, 256 K-bit
Holds status data, panel data, 256 K-bit
a lithium battery.
8-bit parallel interface IC
CR motor driver IC
PF motor driver IC
Head fan (HF) motor controller and driver IC
LA 3B
1A --
2°C

Figure 1-16. ROMA Board

7 A 7B 9 A 1 0 A 1 1 A 1 2 A
i
1-27
13A
14A