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Programmable Hardware Manual (PHM)
© Tibbo Technology Inc.
"Programmable Hardware Manual" provides an initialization example for the LCD. See
THE REFERENCE -> Platforms -> EM2000W -> Working with the LCD
.
4.1.1.12
External Keypad support
The EM2000 module supports both matrix and binary keypads. A typical matrix
keypad is shown on the schematic diagram below:
Due to flexible scan and return line mapping provided by the keypad (kp.) object,
you can assign any combination of GPIO lines to connect to your keypad. Up to 8
scan and 8 return lines can be assigned. On the EM2000 module, all scan line must
be configured as outputs, and all return lines — as inputs.
To build a keypad you will need to have at least one return line. A sensible count of
scan lines, however, starts from two! Having a single scan line is like having no scan
lines whatsoever — you might just as well ground this single scan line, i.e. always
keep it active: