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The attached file contains a design voor a DCC controller shield to accomodate a NANO or 328 with boorloader.
As this is my first design maybe someone could have a look and see if i stumbled into some pitfall.

* Arduino_Nano_V01.pdf (105.12 KB - downloaded 53 times.)
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Hey!  Tell us more.   Scale, how to use etc.  Looks interesting :-)

David
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Dr. David Harris
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The SD card may not be reliable with just voltage divider for signal level conversion.
Recommend add a buffer powered from 3.3v with 5v tolerant inputs, such as used here:

http://www.ladyada.net/make/logshield/design.html
http://www.mouser.com/ProductDetail/Texas-Instruments/SN74AHC125N/?qs=sGAEpiMZZMuiiWkaIwCK2UHhUsuHvyUOwPyIialPONc%3d
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Hey!  Tell us more.   Scale, how to use etc.  Looks interesting :-)

David

The idea is to have a controller like the Märklin Turntable controller butr then for DCC and to be used in a bigger scale such as O and 1.
I allready worked for some years on this idea but with the Arduine programming became a lot easyier then with a PIC and bare AVR.

There's no blog yet on the progress on the project but there will be one in the near futher.
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The SD card may not be reliable with just voltage divider for signal level conversion.
If i look here: http://www.mikroe.com/pdf/mmc_proto_schematic_v100.pdf
and here : http://www.kronosrobotics.com/Projects/MMC.pdf then it should work.

The sd card is not intended for heavy use. Maybe only once.
If i can find a system to load the EEPROM true a serial interface from windows then the SD wound be used at all.
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Yes but you will find that these are just one off experiences. Lady Ada sells a wave shield and they went from voltage dividers in the early versions to level converters because they came across so much trouble.
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I am now testing if using TerraTerm terminal i can upload a file to the EEPROM.
Must see is the Arduine Serial.read() can handle this.

In the process i have allready removed all SD card related components. See the file attached.

* Arduino_Nano_V02.pdf (100.98 KB - downloaded 25 times.)
« Last Edit: December 14, 2011, 04:53:52 pm by gharryh » Logged

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