Introduction - If you have any usage issues, please Google them yourself
six electronic password lock used 89s52 (can be 51, 52), 4* 4 keyboard, six digital control, 74ls04 (EC), 573 (8D latches). Note : P2-- Data (573 )---( access digital access control) P1 Choice------ (74ls04 ) P0-- 4* 4 keyboard set up a one-time password (into programming) circuit is simple, This program is for beginners learning will be able to expand password module (CO2 plus 24). Sounds series software wave