Key, Led Circuit - Brother P-touch QL-1050 Service Manual

2.3.2

Key, LED Circuit

- Power supply ON/OFF circuit
This circuit detects the state of ON/OFF of the ON/OFF button. Pressing this button in the
power supply OFF state (LED OFF), LOW signal is sent to the CPU. Then the CPU starts
initializing process and establishes the status of power supply ON (LED ON and ready for
date acceptance from PC). Pressing this button in the condition that the status of power
supply in ON and the status of ready for date acceptance from PC (LED ON), the CPU starts
power OFF process, turns the LED OFF and changes the status into power supply OFF (LED
OFF). Pressing this button in the condition that the status of power supply is ON and now
going on printing, the CPU stops printing, starts power OFF process after reading and
discarding the date sent from PC, and changes the status into power supply OFF (LED OFF).
Fig. 2.3-2 Key, LED Circuit
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