Code request

SweLogan

I am trying to read RPM from my car. Byt i cant get things to work with my bs2.

I juse COUNT on pin 0. But the funny is i get 0HZ wen nothing is connected, but if a just put a wier in pin 0 and the other end in the air and play with it i can get like 3000hz

And from the car i jusing this

PJAllen

· You have a low-pass filter (4K7, 0u1)·in front of the transistor.· That may be effectively attenuating (shunting to ground)·your input.·
· "Spolen" -- what's that?· The coil primary?· The input to the ignition coil is going to be spikes (the output, too), not square-waves.·
· See what happens without the LPF (or try a lower value of C; 2200pF, 1000pF.)

metron9

Here is a link from my posts on the msc board, It has a very nice circuit for making a square wave from an ignition coil as well as background information..

http://www.mcselec.com/index2.php?option=com_forum&Itemid=59&page=viewtopic&t=1075&highlight=

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Think outside the BOX!

metron9

Here is a link from my posts on the msc board, It has a very nice circuit for making a square wave from an ignition coil as well as background information..

http://www.mcselec.com/index2.php?option=com_forum&Itemid=59&page=viewtopic&t=1075&highlight=

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Think outside the BOX!