Vixen/Arduino Standardization HELP WANTED!

[buckanear]

All

Let me tell the group this:

When I worked in the electronics industry as a design engineer there was always a catch phrase that always loomed over the start up of a new design. That was "Paralysis by Analysis".

We can get so caught up in what to do that it takes so long to finally do it. You can sit back and brainstorm all you want and you have nothing but ideas. You have to start somewhere. Where you start and where you end up may not be entirely the same direction or end product. It is not totally impossible that the first ideas are totally abandoned due to difficulties and/or a better way.

If there is to be a concerted effort to have something for Christmas 2012, it needs to get rolling rather quickly. To have something the is reliable and tested and ready for the masses needs to be completed by September at the latest. this allows October to buy parts and assemble and get working by the end of November. We are now in the middle of February and before long June or July will be here and if we have no clear direction it will be too late for a group buy.

My intentions are just that. To start somewhere. It may not be what we all want for an end goal. We don't get there unless we start.

This is how I see where to go:

Leverage what is already available. By that:

1) FTDI has a USB to RS485 module that is either a single 485, a dual 485 or a quad 485 output. With the virtual com posts you have up to four RS485 outputs off of one USB port.

2) Vixen will output either Renard or DMX with appropriate plugin/addin for both. So that is done.

3) Arduino UNO R3 has a availability and can be purchased mail order or through local retailers.

4) Power supply can be the Ren-T or something similar. For dimming of AC powered Strings it will need to provide Zero Crossing. The REn-T can be modified if needed for our needs.

5) Use existing SSR design with the addition of a small inline SSR based on the VO2223A phototriac. Work is already being done on that avenue and very good results have been made so far.

Things left to do and this is the time critical part. Doable and not totally impossible even by a small group:

1) Design and fabrication of shields. I can do this as I have already started down that avenue.

2) Porting of Renard and/or DMX to the AVR processor. If in Assembly, I can help, Right now my C coding skills are poor to nonexistent.

3) testing and more testing. I can help in this.

4) this may sound a bit trivial but it can be a stumbling block. What voltage to operate the UNO at, 3.3VDC or 5.0VDC? Some of the ICs to be used in the shield design may work at 3.3 and not at 5.0. This only means that you complicate the shield design with a regulator and level translation.


I am working towards a Arduino solution to my needs. Again I will share what I do and will also assist the community in anyway that I can. I very well know that if we spin our wheels long enough Christmas will be on us before we know and it maybe too late for 2012 to offer something to the community.


Now lets get to work on something.

just my thoughts.

james

[buckanear]

One of the things that bothered me was that even though these are Open Source projects, a lot of the more fancier boards use SMD processor chips. I'd hope that eventually someone (maybe even myself) could design a through-hole version of most of whatever we decide to use. Ebay sells a lot of the PCBs very cheaply, but few of them are non-SMD. For now, the processors like the 2560 sell for almost what I can get the complete, populated board for on Ebay. Time will tell if these are quality boards or not. When deciding on a particular Arduino, please keep in mind that group buys of the completed boards might be a nice option, as well as for the processor chips for the true DIYer. A lot of the bigger chips probably don't even come in DIL flavors, so group buys are important. Another thought is that except for enclosure considerations, the actual Arduino board size does not have to remain the same as the official board as long as the shield connectors are consistent with the official Arduino if someone were to create something.

steve

Steve

The main Reference Design for the UNO has a through hole ATMega328 instead of the surface mounted part. The USB interface is the ATMEL ATMega16U2. The Arduino platform moved to it over the FTDI USB to serial solution due to auto reset issues that many were having with the FTDI solution. That part is strictly a SMD part as is the FTDI USB chips. The Arduino platform is open source and the board design is open to modification with very few if any conditions. Most manufacturers that have jumped onto the Arduino bandwagon prefer the SMD parts because manufacturing mass quantities is cheaper and easier that way. Here we do maybe 500 to 1000 of any one board per year. In most circles of commercial manufacturing that would not even be considered an avenue to go.

I have the through hole artwork for the UNO R3 through hole design in Eagle. That can easily be modified to what ever we want if there is a market and need to build up one from scratch. We could spin a UNO Pro that removes the USB and insures that most if not all the parts are through hole for those that want to build their own from scratch.

Again there is no hard concrete form factor constraint on the board size. We can make the board 3 inch square if needed. Correct that the shield pinouts and spacing are critical. That really is no issue if Eagle Layout is used. There are standard libraries that already conform to the shield pinouts and spacing. Also shields are limited in size either. They can be larger or smaller. The attractiveness of the Arduino platform is its compact footprint. Sort of a smaller version of the PC104 form factor. It can go about a vertically as you wish with the constraint on the on board regulators current capacity.

james

[DennyMo]

When I worked in the electronics industry as a design engineer there was always a catch phrase that always loomed over the start up of a new design. That was "Paralysis by Analysis".

+1 "There comes a time when you have to shoot the engineers and start production." (I'm afflicted with this condition myself.) Conversely, I've also seen projects spiral out of control due to "Mission Creep" because folks didn't do an adequate job up front of defining what they want to do. I don't think it's quite time to line the engineers up against the wall.

And an apology from me: as I was reading the posts here, I kept wondering "Why the fixation on interfacing Vixen with an Arduino?" Then I re-read the title of the thread this morning. Doh! Sorry if my comments about steering away from Vixen muddied the discussion any. I'll need to start a separate thread to catalog my projects' goals. But I'll keep watching this one to mooch your good ideas that will help me... ;)

[buckanear]

+1 "There comes a time when you have to shoot the engineers and start production." (I'm afflicted with this condition myself.) Conversely, I've also seen projects spiral out of control due to "Mission Creep" because folks didn't do an adequate job up front of defining what they want to do. I don't think it's quite time to line the engineers up against the wall.

And an apology from me: as I was reading the posts here, I kept wondering "Why the fixation on interfacing Vixen with an Arduino?" Then I re-read the title of the thread this morning. Doh! Sorry if my comments about steering away from Vixen muddied the discussion any. I'll need to start a separate thread to catalog my projects' goals. But I'll keep watching this one to mooch your good ideas that will help me... ;)

No problem

I agree it is not time to panic yet. But time does have a way of slipping past you and before you know it is is Christmas time again. I would venture to say that 99% of those here do this as a hobby rather than as a main job. So we all have other things that pull us from a hobby like family, work, honey do lists and everything else that can and seems to get into the way.

james

[P. Short]

A couple of comments...

First, I think that the schedule is off. The target time-frame s/b Halloween, not Christmas. Some of the people here have displays for both holidays, and sometimes use Halloween as a way of getting practice and debugging issues in time for their Christmas display. True, many of these displays are more animatronic than lighting, but the interface to Vixen is probably similar. And some of these still have a significant lighting aspect, look at the threads by goneferal both here and on hauntforum.com (and probably on one of the Arduino forums as well).

Second, I think that the hardware focus should be on shields, rather than on spinning another Arduino mainboard clone. I see that as somewhat of a waste of time, and would have a de-focusing effect.

Third, I think that the focus should be on standalone applications. This plays better into the Arduino's strengths, such as ease of programming, modularity and community support. As such, hardware and software integration are the most important aspects here (not hardware alone, not software alone, but the integration of both). In my opinion the standalone project the ability to play complicated sequences accompanied by audio. This implies a lot more memory than directly supported by the Arduino processor, and some sort of music playback hardware. While all of the bits and pieces are available on various shields out there, I don't think that they have been integrated together in a fashion useful for this application as yet.

Last, my personal focus is on PIC-based projects instead of Arduino, because I have a much better ability to get the desired performance from a given processor by working at the assembler level. So while I'll try to help here in the conceptual phases, I'll probably not be too involved in the design or debug phases.

[Blackbeard]

A couple of comments...


Second, I think that the hardware focus should be on shields, rather than on spinning another Arduino mainboard clone. I see that as somewhat of a waste of time, and would have a de-focusing effect.


Last, my personal focus is on PIC-based projects instead of Arduino, because I have a much better ability to get the desired performance from a given processor by working at the assembler level. So while I'll try to help here in the conceptual phases, I'll probably not be too involved in the design or debug phases.

I didn't mean to sway the conversation by suggesting a clone of any sorts, but more about building the reference designs. That's why I mentioned the cost of processor vs. populated Ebay boards. Until the cost of the ATMega chips drop, building one is out of the question versus Ebay. But the Eagle files are there if anyone wants to design something more complete (meaning main board which incorporates shields on board instead of add-ons).

I've been an assembler programmer for most of my career. I've only just started using C++, and only used C for visual Windows stuff. I'm using the Arduino environment as a learning tool, and for freshening my C and better learning the AVR by reviewing the libraries.

My first thought of using the Arduino was to create my own version of a wireless RGB LedTriks, controlled from Vixen. It's about .0005% done right now. I hope the standardization part becomes more like a CVS/SVN/subversion sort of thing where a proven design (hardware + software) becomes part of the trunk and variations of those are branches. And each branch is well defined by what it is to do, whether it's pixels, dimming by DMX, DMX itself, or whatever. I think the list of targets represents a great start, and there are certainly enough "brains" on this list to accomplish all of them. But just remember, there's a wealth of hardware/software out there already that will do a lot of what this thread is attempting to bring to the front, and if it fits the criteria, it should be adopted as "official", allowing others to branch off of that. To me, that's the way this will really get rolling to meet those Halloween/Christmas deadlines.

Windy today, isn't it? No wait, that's just me blowing a lot of air.

steve

[Materdaddy]

For development work, it only costs a few bucks to make a breadboard arduino clone. I have ordered a couple of these in the past for prototyping work: http://www.appliedplatonics.com/breaduino/

If you don't want to shell out $35 for an arduino and want to breadboard small segments of things that are planned for the shield, this may be a viable option for some people.

Note that you will need some way to get the arduino bootloader onto the ATMega if you order them blank and plan on using an FTDI cable to program the µC. I have the AVR mkII which works like a charm for this purpose.

[Zeph]

2) Porting of Renard and/or DMX to the AVR processor. If in Assembly, I can help, Right now my C coding skills are poor to nonexistent.

In addition to receiving and/or generating Renard and/or DMX protocols....

If there is a goal of directly controlling SSRs, then there would also be need for the code to handle the PWM outputs. This would also be useful for the standalone controller niche.

2.1 Library to Receive Renard data from RS485 to an array (size?)
2.2 Library to Receive DMX data from RS485 to a 512 byte array (or a smaller subset offset by address)
2.3 Library to send Renard data from an array to RS485 (size?)
2.4 Library to send DMX data from a 512 byte array to RS485 (or smaller?)
2.5 Library to dim 8 SSRs to 256 levels, given an 8 byte array

There are variations on this possible; for example the initial Renard receiver could be end-of-line only, or it could be enhanced to use the output and do normal Renard daisy-chaining.

A Renard XX replacement might need 2.1 and 2.5. A standalone controller might need 2.3 or 2.4; maybe 2.5 if it wanted to directly control quad SSRs. Still other hybrids could be supported.

For example - plug in an SD card shield and create a repeater which can memorize a Renard sequence (received via 2.1) and then send it out on cue or repeatedly (via 2.3) to control a cluster without requiring the PC. Or use 2.2 and 2.5 to do the same for DMX protocol and up to 8 local channels using two quad SSRs (AC or DC). Etc.

[Jonpro03]

Zeph,
I love where you're going with this.
I'm ready to dive right in. I can see that everyone is going to have a different purpose for their Arduino which I believe is what the Arduino is all about. I'd like to have the project as flexible as possible, with support for all types of hardware/software. Make it capable of standalone playback but have support for Vixen/serial, etc...

With that said, I do believe there should be priorities for development, starting with essential hardware, then plugin and coms protocols to get the hardware talking to one another, then add support for goodies (wifi, audio playback, etc.).

I think the first place to start is to get the Arduino receiving data. That way we can work on developing hardware before the standalone playback is finished.

Priority	Project	Contributor(s)
1	Renard/DMX libraries
2	RS485/Renard shield output library
3
4
5
6
7
8
9

Where should it go from here?

I'm ready to go and buy an ethernet shield which has an SD card slot onboard, so I'll be able to start work on SD sequencing. :D

[Zeph]

By the way, my suggested first path (RS485 in/out, control of external quad SSR, ZC + Renard/DMX send/receive and dimming libraries) DOES involve shooting some of my internal engineers. I want pixel control, and audio. But I'm OK with pushing the first off until later because there are so many variants to deal with, and the second because there may be a shield which will work, and it can be complicated.

For my own interest, I'm with Phil - I don't feel a need to reproduce the niche handled by Renard hardware, but I'm excited at the idea of a flexible, expandable, C-programmable standalone controller. I was thinking about a Propellor based controller, but the wide availability of shields and libraries for the Arduino makes that even more attractive.

AND I love that the same shield and same libraries may serve both niches.