Let's Make Robots!

displaying numbers

hi this isnt really to do with robots but it is building something with electronics so i thought i'd ask here because i know the users are friendly and someone will probably be able to help me.

so my friend wanted to build a scaletrix track and he's cutting some wood and thats all fine but we are trying to work out how to make a lap counter for multiple lanes. we decided to use picaxe because thats all we really know how to do. so far we have decided on an arch across the track with infra red emmiters and in each slot (it is slot car racing) there will be a hole containing a infra red sensor. the car goes through breaks the beam sort of and the picaxe starts timing. one picaxe per lane so at the end the picaxe chips will know the time for their respective lanes. to keep cost down we hope to be using an 08m if possible to keep the cost down. anyway so the problem is we need some way of displaying the times.

i thought of using the program processing so we could show time difference and positions but i have no idea how to use it (dont bother trying to explain here but if yuo know somewhere that would be able to teach me how to use it with picaxe then that would be great)

so seven segment displays we thought of but they need loads of outputs and using picaxes thet have enough would cost a lot

so a seriallcd display but some one would have to change the wire between the chips to display each timeunless you got one for each lane which again would cost a lot unless they were non serial but agin we have no idea how to use them

so basicly it comes down to lack of knowledge or budget

thanks for reading all this and if you have any ideas or could tell me what you think my best bet is please answer below


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i got it (i've had an epiphany) it starts at the other end i get it 



Well Done. And welcome. Happy racing!

@birdmun could u explain that again and why it doesn't happen to all digits

I wish I could explain it, but, I can't. Namely because I have not put serious effort into flowcharting the code and following it through.

can someone explain why 63 will show a zero because if what birdmun said is true the surley the same thing would happen with every bit and therefore only 2 lights will be on

sureley it would be easier to use a 74HC164  rather than having another whole conversation about the  CD4026 so no one has to explain anything from scratch to me again

Pretty sure you don't even need any programming for this, two CD4026 can count up to 99.

How can you drive a 7-segment display using a CD4026 without programming, Amando?

The CD4026 combines a counter and a 7-segment output driver in the same IC. Depending on the current required by the 7-segment LEDs you might need a buffer or transistor array to boost the current from the CD4026 outputs.

thanks i think i could have another look at that when it comes to actually building iit but programing wise that was in arduino

(i dont thik it will look any where near that good)