Hello All,
I'm new to the electronics world and I am trying to put together an IR break-beam sensor stopwatch with an Arduino Uno, and 7 segment 4-bit LCD display. I'm at the initial part where I put the proper wires into the breadboard, then run the program I found from the project hub section Project hub link ... I used the code that is provided on that link as well...
The only issue I have is the numbers aren't showing up properly on the display. I have attached a picture.... I believe this issue will lay in the program code section of what I uploaded? Though, since i'm so new, I don't know what to look for or start. I basically copied from the copy link, and pasted it into my arduino program on my mac.
In addition, the reason I am making this general setup is to be able to have a race and let the IR break-beam sensor trip the stopwatch timer to start running on the 7 segment 4 bit display, then the other set of IR break-beam sensor at the finish line trips the stopwatch timer to make it stop. eventually i'll upgrade to a better display that can hold memory if I want to race multiple times. Thanks for your help and support. I am rather new to this arduino stuff.
Delta_G:
That's NOT LCD. Those are LEDs. They need current limiting resistors. And you need to pay attention to whether they are common cathode or common anode because that decides whether they turn on with a HIGH or a LOW. But most important get current limiting resistors on each segment or you're going to end up burning up your Arduino.
Aw, yes LED! i don't know why I say LCD!? my apologies. Ok, so I have 8, 200 ohm resistors and tried to set it up that way from a youtube tutorial on sun founder UNO board 7 segment 4bit but I was unable to create a proper connection and I wasn't able to follow the schematic properly. I'll learn about he common cathode or common anode because I don't know what that means and you say it's important. I see that parts of the area are turned on low, and some are high. I'll want them all on high while it's timing. Thanks for your post!
Delta_G:
I don't understand that part. Maybe you misunderstood me.
If you have a common cathode display, then you have one pin that gets the ground and you have pins for each of the segments. Doing a digitalWrite(whateverPin, HIGH) with that segments pin turns on that segment.
If you have a common anode display, then you have one pin that gets the positive voltage and you have pins for each of the segments. Doing a digitalWrite(whateverPin, LOW) with that segments pin turns on that segment.
Oh, well, what I meant by what I was saying is that on the display it seemed some of the sections of the display were higher brightness light, than some other parts of the display which were lower brightness light. That's what I thought you meant by HIGH and LOW was in terms of the brightness or lack there of in terms of the display. The picture I had attached shows some parts lighter and some parts brighter.
Thanks for the common cathode and common anode display explanation. It makes sense. I will find out, as I got it from adafruit.com... I'll check it out and see if it's common cathode or common anode then hook up the segments and ground or positive voltage correctly. Thanks again.
I was wondering, if you google "sun founder uno segment 7 4 bit" it has a description with 8 220 ohm resistors to use and a different wiring schematic than I have... would that be appropriate for my Arduino one? Or are they completely different processors?
