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3.9 Keypad switching & scanning
The keypad interface is a peripheral which can be used for scanning keypads up to 8 rows (outputs
from Port Control Logic) and 8 columns (inputs to PCL). The number of rows and columns depend on
settings of the PCL.
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[Figure 3.9-1] Function key circuit diagram
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[Figure 3.9-2] Number key circuit diagram
Copyright © 2009 LG Electronics. Inc. All right reserved.
Only for training and service purposes
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3. BB Circuit Technical brief
GM310f service manual
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- 39 -
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LGE Internal Use Only
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