Hi I am looking to make a lap counter for a slot car track. I have been looking at using a pair of 4029's to get the two digit lap display in a count up mode. I would also like to activate a flashing light when the first person reaches their lap count. Looking at the 4029 data sheets I see preset jam lines. Are these for presetting the number I would count to via a binary number? The trigger to the counter would be an IR emmitter receiver pair. Ideally I would also like to display fastest lap time for each lane.

Now, I am not a electronics newbee and I am seeing this circuit get quite complicated. I work in the industrial electronics/automation field and worked as an avionics tech doing circuit board repair and troubleshooting about 20 years ago. As these fields electrically are worlds apart my circuit board knowledge is a bit rusty(not to mention things have changed some). Still Ohm's law is Ohm's law. I know I could easily do this project with a $100 PLC (programmable logic controller) and a $450 dollar touch screen, but thats alot of jing for this. So now I am wondering about using a microcontroller and no I haven't used one before. I have written servo programs in basic and am very competent at ladder logic, so I think I could pick it up rather quickly. Learing a microcontroller would open a whole new line of ideas for me. Can anyone recommend a simple inexpensive one?

Also, if i skipped the fastest lap display and just did a lap counter I could make this circuit manageable via a couple of cascaded 4029's. If I did this how would you manage the presets to select the number of laps to count up too?

Thanks in advance, any ideas?

 

In your place I would use an Arduino with a LCD display. Should cost around 50 bucks.
If you use a different uc ( and as a beginner I would not ) do not get suckered into assembly, use some high level language. See: http://www.opencircuits.com/Microcontrollers_for_Beginners

 

You may need a 4511 (digital display decoder) and a MM74HC393 (binary counter).

 

Hey Russ, after about 8 hours of research, I am going to give the Arduino a try. Best part of it is, I talked my boss into buying it. From what I have read it is just simplier for a beginner to get started. There might very well be better options, but simple to get started is the key for me. Quick results will also make my boss happy! I have so many projects in mind for this new found learning experience and can't wait to tackle it. Thanks for your input. I have bounced back and forth between the PIC and Arduino all day. Alot info out there for both. Once I learn the Arduino well I can always tackle the PIC. I also like the fact that the Arduino boards with the chip have all the support components there and they are really quite reasonably priced.

 

I think you will like it.