Christmas in San Jose! - WEB - FB - VIDEOS
Halloween in San Jose! - FB
2015 Halloween Show - Planning now - hopefully some house projection...
2015 Christmas Show - 5x E681-12, 1x 6804, Ren48LSD, 3x RenSS16, 1x Falcon16v2 (w/expander), 24x90 WS2811 pixel MT (James MT Strips), 12x DIYC Floods, SuperPixelStar, 3x Pixel Arches, PixaBulb House outline
Ignorance is Temporary - Stupidity is Forever...
Thanks for the clarification.
I use this one this year and it works great i got it in about days after ordering
even though this is RS-232, can't you just use the $.65 adapter from monoprice, converting from RS-232 to CAT5 and run CAT5 cable as long as you want to? Reason i am asking, i think my OLD laptop won't make it, so i might have to use my newer one, with no serial port and WIN7.
No, converting the cabling/connector type is not the same as changing from RS-232 to RS-485.
The RS-232/RS-485 standards not only specifies cabling and connector types, but defines, primarily, the electrical communications standards. Electrically, RS-232 uses a shared common ground and is very susceptible to noise. This is the reason for the shorter cabling distances. The RS-232 spec calls for cables lengths less 50 feet for the speeds we are using with the Renard devices.
The RS-485 standard does not use a shared ground, but rather a two-wire voltage differential communication protocol. Because of this, it is not as easily affected by electrical noise on the wire, hence the much longer allowed cabling distances - up to 4000 feet.
Long story short, simply changing the connectors on the end of the wire will not change the electrical communication protocol.
Just clarify - you can send RS-232 down cat5 cable and use RJ45 jacks, I was just pointing out that doing that will not convert the signal from RS-232 to RS-485. It would still be limited in the length of cable to the much shorter RS-232 spec.
Here is an post I did last year showing how to build a DB9 to RJ45 cable. Still RS-232, but as long as you set the jumpers correctly, this plugged into a SS24 about 40 feet away, just fine.
Coming out of the first board to the second, third, etc boards will all be RS-485 because of the circuit design and chips used to generate the serial communication.
I read your earlier post about the DB9 - RJ45 cable, and it brought up the question for me, why would I then need a RS-232/RS485 converter if I can go straight from DB9 to RJ485, which you answered in the previous post. Thank you for that. I do have another noob question. I recently watched the following video ( http://www.youtube.com/watch?v=GNW6qKscRyY ) where 2 data wires were connected to the RS-232/RS485 adapter, 3 were connected to power, and 3 connected to ground. I plan to run from this RS-232/RS485 adapter to a SS24 board, do I need to pass power/ground down the cat5 with the SS24 as my first board?
That post was for the Ren 16 Xmus version, which does not have an onboard Power Supply. It gets power from and external 12v source, like a PC power supply. You only need to use Pins 4 & 5 and a ground for most other Renard boards.
Perfect! Thanks again. I found the wiring diagram. I should be all set.
Nice review, makes it easier to make a decision! Here is also some general information about what a RS232 to RS485 converter is and how it can be connected. More like a wiki page.