Hey
Well I thought I would say something about my day in front of the breadboard.
I wanted to learn some about counting circuits so I built a fast astable circuit with a 555 timer, worked fine; connected it to a 4060 Binary Counter, which also worked great; and from the 4060 to my newly delivered 7 Segment Decoder IC (74LS47, or somethin) .. didn't work QUITE as well! Heheh...
Wired my 7 Segment LED display to the decoder, flipped the switch ... nothing! Ahhhh, I checked ALL my wires, all the connections and wired up LED's in different places to make sure the currents and the pulses were all working correctly; which they were. Decided that maybe the signals from the 4060 Binary counter to the 7 segment decoder were not strong enough and wired up some transistors to the outputs of the Binary counter to boost the signal ... still NO joy!
Took the LED display OFF, wired up an LED to one of the outputs of the Display Driver (G node) -- still no joy!!!!
After HOURS of playin around and looking stuff up; decided to take the transistors off the outputs from the 4060 Binary Counter, wire it directly (as first attempt) to the display driver and managed to get an LED (not the 7 seg display) to flash as if it was one of the led's in the display.
Why did the transistors stop the signal, does anyone know ?
Can't do a diagram yet ..
Example:
Bit 4 from 4060 was connected to Base;
Positive terminal on breadboard to Collector
Emitter to input on 7 segment Display Driver
???
Anyway, so I have one LED flashing as if it was one inside the 7 seg display -- this is just to test the circuit was actually WORKING! heheheh -- this took me all day.
RIGHT ... now ... after much head scratching I also discovered what Anode and Cathode means!! ... And my 7 segment display has a common CATHODE, not anode as it should be! DEARY ME! hehehe.
Now I have the thing pretty much working (although I can't work out why removing the transistors helped) exept it is just one led and not the 7 seg display ... so ... because my display is a common cathode I cant use it ... is there any way to get around this ? I mean, reverse the polarity ?? I know that there isn't a way to make the LED's in the display work the other way round, but is there a way to convert the signal from the display driver so it works with a common cathode 7 segment display ? (I have a common anode ordered, shoudl be here on monday, but I can't wait .. I need to check this stuff out! heheh)
ANYWAY
Eventful, head scratching, eureka day.
-Happs
EDIT: the right word is probably .. invert.
Well I thought I would say something about my day in front of the breadboard.
I wanted to learn some about counting circuits so I built a fast astable circuit with a 555 timer, worked fine; connected it to a 4060 Binary Counter, which also worked great; and from the 4060 to my newly delivered 7 Segment Decoder IC (74LS47, or somethin) .. didn't work QUITE as well! Heheh...
Wired my 7 Segment LED display to the decoder, flipped the switch ... nothing! Ahhhh, I checked ALL my wires, all the connections and wired up LED's in different places to make sure the currents and the pulses were all working correctly; which they were. Decided that maybe the signals from the 4060 Binary counter to the 7 segment decoder were not strong enough and wired up some transistors to the outputs of the Binary counter to boost the signal ... still NO joy!
Took the LED display OFF, wired up an LED to one of the outputs of the Display Driver (G node) -- still no joy!!!!
After HOURS of playin around and looking stuff up; decided to take the transistors off the outputs from the 4060 Binary Counter, wire it directly (as first attempt) to the display driver and managed to get an LED (not the 7 seg display) to flash as if it was one of the led's in the display.
Why did the transistors stop the signal, does anyone know ?
Can't do a diagram yet ..
Example:
Bit 4 from 4060 was connected to Base;
Positive terminal on breadboard to Collector
Emitter to input on 7 segment Display Driver
???
Anyway, so I have one LED flashing as if it was one inside the 7 seg display -- this is just to test the circuit was actually WORKING! heheheh -- this took me all day.
RIGHT ... now ... after much head scratching I also discovered what Anode and Cathode means!! ... And my 7 segment display has a common CATHODE, not anode as it should be! DEARY ME! hehehe.
Now I have the thing pretty much working (although I can't work out why removing the transistors helped) exept it is just one led and not the 7 seg display ... so ... because my display is a common cathode I cant use it ... is there any way to get around this ? I mean, reverse the polarity ?? I know that there isn't a way to make the LED's in the display work the other way round, but is there a way to convert the signal from the display driver so it works with a common cathode 7 segment display ? (I have a common anode ordered, shoudl be here on monday, but I can't wait .. I need to check this stuff out! heheh)
ANYWAY
Eventful, head scratching, eureka day.
-Happs
EDIT: the right word is probably .. invert.