Dual programmable keypad code lock using PIC18F452

Quick Solutions to Questions related to Dual programmable keypad code lock:

• How many keypads can be connected?
  Up to two keypads may be connected to drive both relay outputs.
• What type of keypads can be used?
  Professional, outdoor or other keypads may be used.
• How are the relay outputs configured?
  Relay outputs are configurable as output voltage from +6 to +24VDC (from power input) or as simple switch emulation.
• Is the small LCD required?
  The small LCD is optional and can be omitted.
• What is the power consumption?
  Low power operation uses only 4 to 8 mA at 12VDC with internal switching regulator and microcontroller auto sleep mode.
• Can the secret codes be changed by the user?
  Yes, the 4-digit secret codes can be changed by the user; the previous code is needed to change it.
• What happens after multiple wrong attempts?
  The system auto blocks after 5 wrong attempts.
• How do you activate relay outputs?
  Type the 4-digit code and press # to activate relay output 1, or press * to activate relay output 2.
• How do you change the secret code?
  Type the previous code and press # or * until the piezo sounds (after 5 seconds), then type the new 4-digit code and press # or * to finish.
• Are firmware and design files available?
  PIC hex file, PCB layout and schematics (Eagle) are available; source code (CCS C) can be purchased separately.