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budude
06-04-2011, 02:25 PM
One thing I think this project may need at some point is a daughterboard extender that will allow you to place the daughterboards at a significant distance from the PropController main board. Greg has this capability on his Helix and it's a great idea. My thought is that it would have the 8-pin SIL connector at one end and an RJ-45 at the other. We could transport 3-signals over 3 pairs and supply power over the other pair. Of course, you would need a set of two for each daughterboard.

I'll look into drawing something up for this.

DynamoBen
06-04-2011, 02:29 PM
My thought is that it would have the 8-pin SIL connector at one end and an RJ-45 at the other. We could transport 3-signals over 3 pairs and supply power over the other pair.

Greg's transports 3 I/O pins if memory serves, are you thinking 3 or 4?

chilloutdocdoc
06-04-2011, 02:29 PM
Was the data sent via a RS485 interface or something? This would totally alleviate about half of my controllers in the show if I could do this.

budude
06-04-2011, 02:59 PM
Greg's transports 3 I/O pins if memory serves, are you thinking 3 or 4?

It would have to be limited to 3 pins because the extender power has to be supplied via the RJ45 as well. I think this will be OK for most boards. I was thinking of RS-485 but I suppose it could be RS-232 if you wanted more I/O pins transported.

DynamoBen
06-04-2011, 03:11 PM
It would have to be limited to 3 pins because the extender power has to be supplied via the RJ45 as well. I think this will be OK for most boards. I was thinking of RS-485 but I suppose it could be RS-232 if you wanted more I/O pins transported.

I knew at some point I would pay for adding that extra pin to each header. ;)

chilloutdocdoc
06-04-2011, 03:25 PM
What about using 2x rs485 lines and transporting all of the pins?

budude
06-04-2011, 03:53 PM
What about using 2x rs485 lines and transporting all of the pins?

Hmm... Personally, I'd rather stick with a single wire - if we need four lines it might be better to use RS-232. I know it will limit the distance and require a different board but I think the benefits would outweigh the requirements of always having to have two cables. Which boards require 4 wires at this point? I know for the LSD port that I only need three - the 32-channel dimmer has all four but - and I'm not sure how/why it's used - but the fourth wire goes to the SSR outputs?

DynamoBen
06-04-2011, 04:10 PM
the 32-channel dimmer has all four but - and I'm not sure how/why it's used - but the fourth wire goes to the SSR outputs?

I know why, and I guess I should tell people this, the fourth I/O is for a 1-wire temperature sensor.

chilloutdocdoc
06-04-2011, 04:10 PM
True, if you really need more wires I guess you could use a bcd decoder or a shift register, would slow down the.data, but more pins for less wires.

budude
06-05-2011, 04:20 PM
Well... I'm open to suggestions regarding which chip(s) to use for this. Maxim has a quad driver chip but it operates at 3.3v. This is fine for the Prop side but I am planning to transport 5v, not 3.3v to the far end so this would not work. The 3.3/5v-either versions are wicked expensive - like $10-12 PER chip - way too much... I didn't really want to do an SMD version to make it simpler to make (ideally single-sided home-etch if possible). I was also hoping to make the two ends the same as well to save some confusion.

I think the 65LBC179 might work using 5v supply on both sides and it seems like it would support 3.3 or 5v logic? I realize it would take 3 of the chips at each end but the chips are easy to find.