tachometer

Hello,

Does somebody have a good idea how to implement a tachometer on the
mini2440 while running the linux kernel on it? (with activated gpio driver)

Hello,

for low speed ones, you may write a routine to continuously check gpio (and
count upon level change).

for medium speed ones, you may search to find any unused external
interruptable gpio pin (that hope its device driver be available).

for high speed ones, you have to implement an external counter ic (i.e. a
uC with configured counter pin) and then read it using uart (or may
available i2c or spi on gpio).

regards
www.dadehabzar.ir

I need high speed since the board is intended to replace my current i386
based datalogger on our tractor-puller so an uC sounds like the best
solution, I have a couple of rpm's to watch so the uC also takes the load
of the board.
Thanks.

Try this for some ideas:

http://www.avrfreaks.net/index.php?name=PNphpBB2&file=search&mod...

if going the 8bit route.