Noise comming fron VW Gol Engine

[NikZetaJones]

2001 vw gol

Hello,

I'm making a tachometer which communicates with my VW Gol Computer. The only problem I have is that the Enginse "nosie" is getting into my AVR power supply (made with a LM7805) and possible the AVR I/O pins. How can I filter this noise from the Supply and the I/O Pins.

Thanks very much
Ezequiel

 

[mystery]

7805 gives a very bad performance for noise figures , instead i recommend you to use Switched mode regulator like LM2575, you may also use LDO regulators like LM2931

How do you communicate with the vW Golf Computer , is it over CAN bus , do you have any protocol?

 

[NikZetaJones]

Thanks

The communication is using RS232 and a special protocol.

Bye
Ezequiel