Main Pcb Block Diagram - Brother HL 1240 - B/W Laser Printer Service Manual

1.2

Main PCB Block Diagram

HL-1240
Fig. 3-3 shows the block diagram of the main PCB of the HL-1240 printer.
Reset Circuit
Program + Font ROM
1.0 Mbytes
RAM
(2.0 Mbytes)
EEPROM (128 8 bits)
CPU Core
(MB86833)
BUS
INT
To Engine PCB
Fig. 3-3
3-3
CHAPTER 3 THEORY OF OPERATION
A S I C
Oscillator (32.7MHz)
Address Decoder
DRAM Control
Timer
FIFO
CDCC Parallel I/O
USB I/O
Soft Support
EEPROM I/O
Engine Control I/O
To PC
To PC