Main Pcb - Brother LX-200 Service Manual

5.3 Main PCB

Fig. 5.3-1 shows a block diagram of the electrical parts.
The Main PCB comprises the CPU, detector circuits (including switch status detection),
motor drive circuits, and power circuits.
Main CPU
The main CPU is an 8-bit CMOS microcontroller that controls the overall system.
The main CPU incorporates 256 kB RAM, 8 kB ROM, and 56 I/O ports.
The I/O map for the I/O ports is shown in Table 5.3-1 overleaf.
Fig. 5.3-1 Block Diagram of the Electrical Parts
5-4
Corner Cutter
Motor (TC)
Paper Size Detector
Motor (Y-CA)