New renard design - Renard X

[ccates]

Hi,

I have created a new Renard pc board design that some of you might be interested in. It is a small board with just the PIC,Oscillator and output jacks on it. It would use another board for generation/translation of the data and ZC signals. Each board gives you eight outputs. The boards could be daisy chained (or stacked) to produce any number of outputs within reason. I am calling it the Renard X. Attached is a simple block diagram (RenardXblock.gif).

The advantage that I see to this design is that is allows you to add additional channels without having to duplicate the Data/ZC/Power circuitry.

I have produced a preliminary design using ExpressPCB (www.expresspcb.com). It is designed to be a single sided board using jumpers on the top but it could also be made double sided. It is included as RenardX_osc1.1pcb

Due to time constraints I haven't been able to test this board yet but I plan to soon. If someone else would like to try it please feel free. I offer this board design to anyone who would like to use it.

If you have any questions please leave a comment or email me at cates\at/ eritter.net

[xmus]

see attachment, for those of you who don't run windows (phil) and others who don't want to install the pcb tool (i had to upgrade, apparently this is the new version of express pcb tool).

Right angles on traces aren’t advised (unless going through a via) due to thermal expansion. A more robust design would use curved or larger angles. So for example, lets say your trace wants to take a right turn, turn 45 degrees, then go a short distance, and turn 45 again.

I assume in your design folks would need to run the following signals to the board, but no RJ45 jack is provided: ZCin, UARTin, UARTout, ZCout, groundIn, VCC(5V)In, VCCOut, groundout. I see some installation complication, in having to solder the above to the board, or having to put external connectors on all those. Why not just use RJ45 jacks?

Not to rain on your parade, but, UART is only capable of going very short distances (20 feet max would be my guess, similar to RS232), the purpose of converting to RS485, and then back to UART, is to overcome the limitation of 20 feet or less between controllers.

I think the Renard 8 that Phil designed, is something you should have a look at, considering mostly the above paragraph.

Not to be hard on you man, nothing personal, just my opinion. Not trying to detour you, keep learning, keep digging, and please keep right on designing.

Thanks,
Dave

[xmus]

Suggestion for reducing the size by 50%:
turn the RJ45 jacks 90 degrees, put them back to back at the very bottom of the board, slide the pic chip down a good 1/2 inch (as far as you can), and bring the osc down until the top of the osc package is below the top of the pic package..... then move all those ZC,serial etc signals down to go to the left of the pic.

[P. Short]

To be honest, I don't particularly like the idea of running TTL-type signals from one board to another in such an ad-hoc manner. I worry about the integrity of the signals ... will they remain clean without hoise and edge degradation, will the grounds of the chips end up the same level, will power remain clean, and so forth. They will probably work if there are only a few of them connected together, but I would only use this design to play with a little bit before going to one of the coop boards.

--

Phil

P.S. The output of the oscillator is going to the wrong pin on the PIC, there is an open on VCC in the lower left corner, and the trace on pin 9 of the PIC seems a bit skinny. Also, there should probably be a power supply bypass capacitor.

[xmus]

Maybe this is what you meant Phil, but there should be a cap as close as possible to the input voltage/ground of the pic as well.

[P. Short]

Yes...best placed as close to the PIC as possible (and oscillator as well).

--

Phil

[ccates]

Thanks for the suggestions guys. I am a novice at proper pc board design so the comments from the more experienced are greatly appreciated.

My idea is that these boards are appropriate for mounting very short distances from each other and from the ps/zc/data board (e.g. inside a small case). The boards and a ps/zc/data board would give you an expandable unit.(i.e start with 2 boards to get a 16 ch then expand it with two more to a 32 and so on)

I did not feel that a connector would be needed between boards as the lead length would be fairly short. Expansion to another site would be done with the ps/zc/data board supplying the RS232/RS485 signals to another unit. If you put the boards very close together or stacked them the distance the TTL level data signal path between PICs would be very short . I never planned for the TTL signals to go more than .5 inch or so between boards

I knew this design would probably have problems so I wanted more experienced eyes to look at it. Thanks for catching my errors so fast. I can't believe I forgot the decoupling cap and got the osc pin wrong. I am going to fix the errors and experiment with it and see how far I can push it.

Please understand that I am in no way disregarding the fantastic work that has been done on the all of the Renard boards. It is a fantastic design. I applaud all those involved.

I hope I haven't stepped on anyone's toes. If so I offer you my humble apology.

Thanks!

ccates

[xmus]

No offense taken at all, thanks for not taking offense to our criticism! Take another stab at it. So, what exactly are you trying to do then? You will make a Renard system, that has ZC/PS units co-located with your Renard design, and the idea is lots of them would be in one small place, and you would use them with Sean Bowf's SSR board as well? Give us a feel for the overall layout, and number of channels (and where) do you currently have a setup? If so, what is it based on? Are you starting from scratch? Big property? small? shaped like?

[Macrosill]

When designing a new pcb we would ask to follow the guidlines posted in the wiki.
http://christmasinshirley.com/wiki/index.php?title=Hardware_Design_Guidelines

[P. Short]

Yikes...no mounting holes...lol.

--

Phil

[xmus]

Yikes...no mounting holes...lol.

--

Phil


You crack me up phil :) You never did put holes in your Renard 8 did you? I was looking at it, and thinking "double sided sticky tape? Rubber band over the top?." But don't worry the xmus board has 6 mounting holes! That is enough for both of us (minimum spec is 3!).

I like the guidelines though, they look good. Should we add a section for the standardization of the Renard RJ45 in/out jack as well? I see the SSR RJ45 jack is on there....

[ccates]

Hi,

I'll try to make my idea a little clearer.

My setup I am trying to make this year has two sites separated by about 150 ft.
In the first site I will have a mega tree with 16 ch and about 16 other channels for a show to go with "feliz navidad". The other site will have about 16 channels of assorted lights and animation(no music). Both sites use Sean Bowf SSR boards remote located as necessary. Each site will have its own PC controlling it.

Current designs as I understand them allow me to go two ways:

1 . Use 4 of the Ren8 boards at site one and two more at site 2 giving me 48 total channels. This option requires me to duplicate the RS232/RS485 circuitry and so on on each board.

2. Use 1 Ren64 at site one and 1 Ren64 at site 2. Do these boards have to be fully populated or can they be made to work with less channels?

Now lets say next year I want to add 48 more channels to site 1 taking me to a total of 80 channels at this site. All of the these channels are still to be within the same box. My options to expand this site are:

1. Add 8 Ren8 controllers.

2. Add a Ren64 at site one. I don't need those extra channels though.

My idea is to add an additional option. With this system I would build 1 PS/ZC/DATA board for the box at each site. The first year I would also build 4 of the controllers for site 1 and install them in the site one box giving me 32 channels.The site two box would get a PS/ZC/DATA and 2 of the controller boards. I have met my requirements for this year and I don't duplicate any components.
Next year I simply add 6 more controller boards to my site one box. Again no duplicated components.

In short my idea is to make a unit that can be expanded without duplicating parts.

Thanks again guys for the help!

Craig Cates

P.S. oops - mounting holes! Well, I did say originally that it was a preliminary design. Thanks for the constructive criticism!

[xmus]

Yes i think you can do the 64 designs and only populate the first X channels (especially if you are using two PC's and there is nothing downstream).

A co-op is A LOT OF WORK. If you going to do a co-op board, or design your own, so you don't duplicate $20 worth of hardware, let me warn you, you are in for hundreds and hundreds of hours of work and logistics. You better be madly in love with your design to justify the effort.... because in the end, any cost accountant will tell you it was a "loss" on paper.

[ccates]

Gosh, I didn't think I ever implied that this board was ready for a COOP or that I was considering making one in the future. I certainly wasn't thinking "Hey I can make money on this". I just thought it was a different way of thinking about the Renard that I wanted other people's opinion on and maybe some coaching with. I'm sorry if I made anyone think anything different.

I'll try to fix the mistakes you pointed out and give it a go. I'll let you know how it works out.

Craig Cates

[xmus]

again, no offense taken, if you really like your layout, you might consider doing a solder on self-etch design.

And, by the way, we don't make money on co-ops, we TRY to break even :) And sometimes we succeed :)

[ccates]

Well, I knew about coops from being involved with the megasquirt community a few years back. I knew they were more a labor of love than a profit making venture.
If you figure your time in it will always be negative profit. I have a full time job already and a small farm to run so unless there was a LOT of interest I wouldn't consider running one even if all the bugs were worked out.

I guess I didn't make it clear from the start that this is an experimental design. Sorry. Does the site have a place for experimental projects that I missed?
If so mea culpa.

I plan on making a couple of boards like this to try out using the PNP blue transfer sheets later this week if I can find the time.

Thanks for the help!

Criag Cates

[JaysonH]

Well, I knew about coops from being involved with the megasquirt community a few years back.

Sorry to OT a little, though, curious.. What is your setup for which your Megasquirt was installed?

[JaysonH]

Woops, I just noticed how old this thread is, it showed up as new for me for whatever reason. :/

[wbuehler]

Phil,

Are these changes still on the scope for this year?

Thanks

Bill

[P. Short]

I'm not sure what you are referring to, since this isn't my project.

--

Phil

[fkostyun]

I think this has really gone by the wayside, as its basically a ren8. if you want something similar (abet more channels) I would go with a ren16 or ren24. The only other option might be a Ren4 (Would need specialized firmware) or Ren8, but, not sure on there usefullness.

If someone wanted individually controllable 4 output boxes, I would say DMX would be the ticket.

[Aurbo99]

Ren64XC5

Is there a mounting hole /drill template available to allow us to mount these to a board or chassis?

Request:... re-do the mounting holes on the next board so they share a common X-Y axis for both Top and Bottom of the pcb. Perhaps a center mount between R16 adn R17 as well.