Large Scale Central

Build your own DCC decoder

This just landed in my inbox on an Arduino mailing list I am on.

http://model-railroad-hobbyist.com/node/19070

Nifty.

Nice. Snagged the code. Not sure I will ever use it but it’s fun to take a look.

Bob, As luck would have it I have most of the parts on hand - I think I’ll give it a shot!

thanks,

dave

David Bodnar said:

Bob, As luck would have it I have most of the parts on hand - I think I’ll give it a shot!

thanks,

dave

Be good to see the results. More and more complex Arduino implementations for model RR use are showing up, which is great. I just started getting into them in the last year, and theyre really powerful. Where else can you get a fully programmable computer with a ton of IO for < $5?

Bob - I got my test units working and have put information on my web page - the unit operates a servo and can also be used to trigger relays or other devices - great fun experimenting!

http://www.trainelectronics.com/DCC_Arduino/

dave

Dave, what the is reason you are using schottky diodes off the power supply?

Greg

Greg - filtering - evidently the fellow who first worked with the circuit had intermittent results till he added the diodes and the small cap in the input to the optocoupler.

When I look at the output on my scope it is cleaner with them…

dave

So the diodes are isolation to allow another stage of filtering.

It would be my opinion that you have insufficient filtering at the regulator.

Very strange.

Greg

Anybody know if the “Massoth” system is close enough to DCC for this to work?

“I thought you were a battery and radio guy!”

Yup! It’s not for my railroad.

Not the diode and cap on the input to the optocoupler, the schottky diodes, one to VCC on the chip, and the other apparently to have the same reference voltage to other inputs.

Greg