Panasonic KX-FP80C Service Manual page 86

As long as these signals remain normal, once the power is turned on, each IC can repeatedly
output 5V (H) and 0V (L). The following shows NG and normal wave patterns.
NG Wave pattern (Refer to NG EXAMPLE)
Normal Wave Patterns
Remarks:
When you use an oscilloscope to judge whether a signal to be tested is normal or NG, perform
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