Casio UP-250 Technical Manual page 47

Circuit board block diagram
The main circuit board unit contains the following electrical circuits:
Power supply circuit
Reset circuit
CPU [internal RAM: 16K bits (2K x 8 bits)]
Memory [EPROM: 512K bits (64K x 8 bits)]
Operation panel control circuit
Drawer kick-out driver circuit
Print head driver circuit
Paper feed motor driver circuit
DIP switch read circuit
Various detector circuits
Carriage motor driver circuit
Auto-cutter driver circuit
The interface circuit board contains the following:
Reset circuit
Host interface circuit
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