I am building a race timer and tree for slot car drag racing. I am using optocoupler modules to read when the car is blocking the sensors at the start of the race. Once the car is staged and blocking the sensor I have separate nano that operates a drag racing tree that shows that the car is stage…

Help us help you. Please follow the advice given in the link below when posting code, in particular the section entitled 'Posting code and common code problems' Use code tags (the </> icon above the compose window) to make it easier to read and copy for examination [image] How to…

I am using 2 Chanel’s on the oscilloscope one is triggered when sensor goes from low to high and one is is triggered on an output pin that digitalWrites high when that event is true. I am new to this forum. But when I figure out how to post a picture I will post a picture of my fastest times and my…

[image] shawnmart: But when I figure out how to post a picture You would be better off figuring out how to post your code, and doing that. Pictures are not worth 1000 words. We can trust you to use your oscilloscope, and we don't doubt your findings. a7

[image] Yellow is sensor trigger and blue is D/O pin trigger. This has about 3 ms delay. My readings range from half a ms to around 20 ms between both. I would think this is because of where in the loop the arduino is when the event occurs. It seems like the form is only going to let me post o…

[image] Fastest reading here. But for the most part they are 3 to 20 ms apart.

Have a look into port manipulation. This page gives you some basic info: https://create.arduino.cc/projecthub/Hack-star-Arduino/learn-arduino-port-manipulation-2022-wokwi-systems-simulat-10f9af There's a lot of good videos on youtube which explain it better though.

I have tried the pin change interrupts but my problem is when the cars pass through the optocouplers the car breaks the beam and an interrupt occurs then the car leaves the beam and a second interrupt occurs. I just need the micros at the exact time that the first interrupt goes from high to low on…

Where is your code? How can we troubleshoot this issue without seeing your code?

No one can help you without seeing the code. POST. YOUR. CODE.

[image] Make experienced users help: two ways to quickly post code as a code-section Tutorials Hi newcomer, This thread wants to show you how you can speed-up getting helpful answers with small effort. If you manage at least to post this way. You have the sym…

Slot car timer problems

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StefanL38 November 18, 2022, 8:29pm 20

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Slot car timer problems

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