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Topic: LCD and Keypad sharing data pins (Read 3365 times) previous topic - next topic


Updated sketch here: http://www.phpbbireland.com/kiss2/viewtopic.php?f=80&t=265

Features:
  • Allows three different passwords...
  • Lockout if tampering (allows three attempts and then lock the keypad for X seconds)...
  • Uses a piezo device to generate keyboard tone and door open tone...
  • Backlight off if inactive, any key to turn on backlight...
  • Software driven contrast (user can set level)...
  • Latched output (relay 3 seconds)...
  • A test menu with some options (just testing)...



Why not just use a couple shift registers (one for the display, one for the keypad)?  This method would only use 6 pins (or less), cheap (like $0.50), and to me far easier to make and program.  Heck, you could even make the individual keys lighted and still have pins left over.

Tim
Arduino - Teensy - Raspberry Pi
My libraries: NewPing - LCDBitmap - toneAC - NewTone - TimerFreeTone

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