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michaelahess

Cheaper USB to 485 Adapter

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If I grab this:



http://cgi.ebay.com/RS485-RS-485-DB9-Serial-USB-2-0-Adapter-Converter-/180533603407?pt=LH_DefaultDomain_0&hash=item2a08a42c4f



And wire pins 4 and 5 from the RJ45 on my controller to pins T+/B and R+ (or something like that) along with pin 6 to ground on the serial adapter on this product, will it work?



My kids, lost, stole, threw out, ate, my current LOR adapter and LOR want's nearly $50 for a new one.

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michaelahess wrote:

Yeah, but it's $17 for shipping.


Not really, Dan has stated many times that the shipping calculator in the store "estimates" shipping charges on the high side.

LOR will only charge the actual shipping cost, which in this case will probably be much less for this item.

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Good to know, I just got a response from Dan stating the same thing. Fortuantely I found the adapter at the bottom of one of my kids toy piles!



I'm still curious though if the item I linked to would work. I've read a few other posts on here about it, but it seems that very few folks bother making them. I always make my own adapters, a side affect of being in the telcom industry I guess, and would like to keep a "cheap" spare for "just in case" situations.



Thanks for all the quick replies!

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Well, since you found yours, and can get the show running without the additional pressure of a lost adapter, why not order the one from ebay and see if it will work.

My understanding is that it is not just a gender changer, but also has "certain" electronic components in it.

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Right, I think I'll do that. I'll let everyone know how it works out.



Anyone know the pinout of the RS485 to DB9 Serial adapter LOR sells? I figure that would be wired the same on the DB9 at least. Then a simple RJ45 to serial adapter for a quick breakoff connector.



Heck I could wire that into my outside wall with a nice watertight enclosure so I have a hardwired pass through. Ah man, the ideas are starting again, the wife never likes that. :)

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Did the shipping end up being $17?  I lost my adapter and am in the same boat now.  doh.

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I have a cheap one from eBay and it works fine.  It's actually meant to be a USB to DMX adapter, but of course DMX uses the RS-485 protocol.  If you want to run an 'enhanced' LOR network, you need to make sure the chip in the adapter is the FTDI brand, and that it is a genuine FTDI, as there are a lot of counterfeit FTDI chips out there, and FTDI has changed their drivers to detect the counterfeits and not work properly.

As I understand it- DMX uses a kinda oddball baud rate of 250,000 which the FTDI chip supports, but most other USB to Serial chips (Prolific, CH340) do not.  Thus any RS-485 adapter meant for DMX should, in theory, use the FTDI chip.  But again, beware of counterfeits.

And DMX uses a different pinout on the RJ-45 connector than LOR, but I see you're already on top of that.

 

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i am  making one now  using this type of adapter which colors you did you yous pls white blue +  blue -

 

USB-to-RS485-USB-485-Converter-Adapter.jpg

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Just thought I would clarify that there are electronics between the DB-9 and the output of the RS-485, it is NOT simply a wiring conversion......

Greg

Edited by a31ford

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