Combination Lock Circuit PIC16F628 Hi Tech C

@ Profahmet teacher previously had shared projects a combination lock on the hitech picc thought it would be a good example of programming with c language can be an example for people who can give limp and PCBs have drawings of the project’s source code.

Combination Lock Circuit User manual

# The default code is “1111” # (EEPROM microcontroller in nenaprogramovano first power supply)

# “New Code” old password “*” to change the code by typing a new code

# Enter the code: “Code” #

# Only four digit codes (current firmware) accept lock

# Enter, press “#” to serve as an Enter

# Button “*” is used to change the code

Even if the password is stored in the EEPROM is stored in the microcontroller is not affected by power outage

As a control element is used PIC16F628A microcontroller or an older type of PIC16F84A ( see paragraph below : mounting variants) . They are accompanied by the indication LEDs, transistors through the relay

The source is solved simply assumed DC voltage supply . At the entrance is a fine surge protection in the form Transil and insurance . Furthermore, there is a stabilizer 7805 in the classical circuit.

The output element is a relay that always correctly specified code changes state . Closed state is indicated by a green LED . If the relay is open off any indicator . This is because the device was originally designed for the control of small control panel via an impedance balanced loop and arming status – relay open – the required minimum order . For this application , there is a left and a resistor R3 ( typically 1k ) , which served as a balancing loop for the alarm system. If you want to use only the relay , it is possible to replace the resistor jumper. This is brought out to the terminal directly contact NO for free use ( subject to the maximum switching current and voltage).

Source: http://firma.puhy.cz/kodovy-zamek PIC16F628 Combination Lock Circuit Alternative link: