Difference between revisions of "Universal 4x4 keypad"
From ScienceZero
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[[Image:Hexkeypad.png|thumb|400px|right|Versatile keypad]] | [[Image:Hexkeypad.png|thumb|400px|right|Versatile keypad]] | ||
| − | The versatile keypad uses a PIC16C84 or compatible running at 4 MHz | + | The versatile keypad uses a PIC16C84 or compatible running at 4 MHz to transmit keypresses from a standard 4x4 or smaller keypad over a selsectable interface. |
==Keypads== | ==Keypads== | ||
Revision as of 23:49, 1 April 2009
The versatile keypad uses a PIC16C84 or compatible running at 4 MHz to transmit keypresses from a standard 4x4 or smaller keypad over a selsectable interface.
Keypads
3 predefined keypads, one user definable. Selectable decimal, ASCII or key number output.
Telephone Calculator User defined 1 2 3 A 7 8 9 + 7 8 9 / 4 5 6 B 4 5 6 - 4 5 6 * 7 8 9 C 1 2 3 * 1 2 3 - * 0 # D 0 . E / C 0 = +
Interfaces
- RS-232
- 16 to 43 478 Baud
- Data out and inverted data out for generating standard RS-232 voltages
- SPI
- 83.33 kHz with enable
- Parallel
- 4 bit parallel output of key number
- MIDI
Misc
- Selectable beep/LED
Pin assignment
- RB0-3 = Keyboard row output/Parallel data output
- RB4-7 = Keyboard column input
- RA0 = DATA (RS-232, SPI, MIDI)
- RA1 = CLOCK (SPI), /DATA (RS-232)
- RA2 = ENABLE (SPI, Parallel)
- RA3 = Beeper/LED
- RA4 = Not connected
Connection diagram for keypad
If the keypad is 3 keys wide; leave RB7 disconnected.
RB0---X---X---X---X--
| | | |
RB1---X---X---X---X--
| | | |
RB2---X---X---X---X--
| | | |
RB3---X---X---X---X--
| | | |
RB4 RB5 RB6 RB7
