Hi All,
Before I apply the circuit you have suggested, I encountered a strange situation with 7segment display. The driver IC is 74ls49 (open collector). From my lab I got common anode 7segment display. So on a breadboard I wired the 74LS49 and that 7seg display as following:
Anode of 7seg display to +5V, and the a to g pins of 7seg connected to a to g pins of 74LS49 with 510ohm registors (this limits the current to 5mA for each segment of the 7seg). But here comes the funny part, with all input A,B,C,D of 74LS49 to ground (BCD zero) I see number 8 in the 7 segment!! So my logic got inverted. With 0001 BCD I see mirrored 3 in the 7seg. I am going to check if the lab has common cathode 7seg, that will make life easy. But if there is not, would it be possible to use common anode anyway?
Before I apply the circuit you have suggested, I encountered a strange situation with 7segment display. The driver IC is 74ls49 (open collector). From my lab I got common anode 7segment display. So on a breadboard I wired the 74LS49 and that 7seg display as following:
Anode of 7seg display to +5V, and the a to g pins of 7seg connected to a to g pins of 74LS49 with 510ohm registors (this limits the current to 5mA for each segment of the 7seg). But here comes the funny part, with all input A,B,C,D of 74LS49 to ground (BCD zero) I see number 8 in the 7 segment!! So my logic got inverted. With 0001 BCD I see mirrored 3 in the 7seg. I am going to check if the lab has common cathode 7seg, that will make life easy. But if there is not, would it be possible to use common anode anyway?