Epson PX-8 Technical Manual page 31

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The following is a circuit diagram including the power on/off circuit:
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Fig. 2-4 Power On/Off Control Circuit
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The power-off operation involves the following component functions:
• Microcasette tape drive head unloading
• Microcassette tape drive power off
• P-ROM cartridge power off
• RS-232C power off
• Barcode reader power off
• Speaker power off
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It also controls the emergency power supply which allows the computer operation sequence in
process to be completed and status information to be stored whenever the regular power sup-
ply is depleted.
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