Teclado binário para controlo de acessos de 6 bits, alimentação 12V

Binary access control keyboard. 64 combinations are possible. Code is implemented by red jumpers in the coding board. First row tact-switch inputs "1" bit while second row introduces "0" bit. Input sequence always from left to right. Correct code turns on green led. Reset tact-switch clears last code input. Totally analog circuit. No uP or logic gates. Supply 12V