David M

I'm trying to design a circuit for my local rc car club. I wanted to build a drag racing christmas tree. Intially I wanted the pre-stage lights to light when a button is depressed, starting the 1 miunte count down. At 20 seconds to start the staging lights would light up. Then at 4 seconds to start, the 3 yellow lights would count down sequencially 3 seconds and the green light would finally light up, starting the race. Any ideas on how to do this?

I was thinking of building a basic digtal clock that would count from 59 to 0 using divide-by-10 and a divide-by6 chips. When the 20 mark came around the 2 digit would start the staging lights and so forth. Make any sence, or am i totally off on this one?

If your not sure what a drag racing tree looks like goto
http://www.budpark.com/deducation.asp?page=tree#top

Help would be much appreciated! Thanx!

Nigel Goodwin

It's a project crying out for a PIC! - something like a 16F628 would only require a button to start it and drivers for the lamps, plus the code writing. To make the code even easier you could use a BASIC STAMP or PICAXE, both of which are programmed easily and cheaply in BASIC, and both of which are more than capable for a simple task like this.

pike

This circuit is cirtainly going to require the use of a PIC.

Aren't PICs versatile, ey !!!

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www.winpicprog.co.uk - Great PIC language tutorials.

mc_pro1

Hi David M
I run R/C drag cars too

1 the prestaged and stage lights light on when the car is go to the line detected the tire (Body in RC) by the photocell, photoswitch etc not mechanical switch.
2 the sequential count down time for 3 yelow bulbs to green is .5 sec for normal or bracket racing 1.5 sec total no 3 second, and .4 for "Pro light"
Full tree
3 for clock you need a .001 resolution timer when minimun of 5 digit 9.9999 no minutes timer !!!
4 the timers start when the car move in the line when the staged light is off

if you only need this, you make it whit electronics circuits, but if you need more Reaction time, Speed, Handycap 6ft, 33ft 1/8 time you need a microprocesor, memory, eeprom, programing project.

I Design and build similar circuit in 1981 for Scale Drag Racing, and at present work whit it, maybe I can help you whit some circuits !!!!

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mc_pro1
Best Regards
Thanks