's Forum Archives - General

Archive Home >> General(1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 )

Schematic for cycle computer?(5 posts)

Schematic for cycle computer?D1234
Dec 26, 2001 8:00 AM
Anyone know anyone who works for a cycle computer maker or has access to a schematic for any cycle computer?
Any info greatly appreciated.
re: Schematic for cycle computer?firstrax
Dec 26, 2001 10:26 AM
Most of the computers are based on Microchips 16 series chips. A schematic wont do much good without the source code.
What are you trying to do?
re: Schematic for cycle computer?D1234
Dec 26, 2001 10:51 AM
Thnks for the message back. I'm simply trying to replace the extermal magnet sensor with an IR detector and use it to start the ride timer- hold the signal hi or low depending on what is the existing circiut- and then have the ride timer stop on another ir signal to the sensor. Basically I want to disable the need for continuous magnet pulses input and start and stop the timer based on the added IR sensor- don't ask why- just a silly idea.
Thanks for anyother info
re: Schematic for cycle computer?firstrax
Dec 26, 2001 6:11 PM
You dont need the schematic. The magnet sensor is a N.O. reed switch that gets pulled closed every time the magnet passes. Replace the magnet sensor with an IR detector. Use a FET output device. TTL outputs have too high of an on resistance.
Radio Shack has little books by Forrest Nimms called "engineering notes". The one on optical circuits should have some usefull ideas.
Ride Timer?Andy M-S
Dec 27, 2001 6:42 AM
Why not just use a stop watch? If you're looking to time some kind of interval by passing IR beams (or something like that) it seems to me that it would be much easier to adapt an electronic stopwatch, which uses a single set of NO contacts to signal both start and stop. Wire your IR circuit across these contacts and you're all set...