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Topic: Controller Board for Adafruit's Large RGB Matrix Displays (Read 177610 times) previous topic - next topic

Re: Controller Board for Adafruit's Large RGB Matrix Display

Reply #45 –
Regarding #define as proposed by lcunha: This would be great. However, I don't think that this is supported in  Teensyduino.

Re: Controller Board for Adafruit's Large RGB Matrix Display

Reply #46 –
[quote author="lcunha"]How about something like option 3, but using #define?[/quote]

That would be ideal, but unfortunately as MarkusL said, it doesn't work.

[quote author="MarkusL"]in this specific case, there are only two possible options: 16x32 and 32x32[/quote]
Later on I think 16x64 (two 16x32 panels in series) will be supported.  There are 32x64 panels available from China.  Those and other configurations could be supported with a lower color depth in the future.  But you're right, I think just a few standard options should work for most people, and hackers can hack away on their libraries.

[quote author="MarkusL"]I'd also keep it lean, just adding basic functions like drawPixel(), everything else like drawText() or drawLine() should be in a separate library[/quote]
I have everything in one library right now, why do you think this is important?  I don't feel like there's any shortage of program memory on the Teensy 3.

Re: Controller Board for Adafruit's Large RGB Matrix Display

Reply #47 –
Of course you can also put it in one library. I just like it when functionallity is seperated: Everything that is directly related to interfacing the panel in one, and helper functions like draw line in another, for example like the adafruit Adafruit_GFX and Matrix libraries. This can make reuse of the parts easier.

Re: Controller Board for Adafruit's Large RGB Matrix Display

Reply #48 –
[quote author="MarkusL"]I just like it when functionality is separated[/quote]
Got it, I considered that, but given this library is my first C++ class (I'm used to writing software in plain old C), I didn't want to make it more complex than necessary.  The first version of the library was written in C, and I separated the source into modules for drawing, for the text layer, etc.  I had to add all the methods to the single matrix class when moving to C++, but kept the source files separate.  Maybe in the future I'll come back to pulling functionality out into separate classes.

Re: Controller Board for Adafruit's Large RGB Matrix Display

Reply #49 –
Quick update: I packaged up the library using a unique header file name per configuration.  I finalized the features for the first release, and made an example program that does a demo of all the features.  A few beta testers have a copy of the library, but I still have some work to do before its stable.  I just moved to a new apartment this weekend and all my stuff is packed up, so I probably won't make any progress in the next few days while I get settled.  The kit is hopefully close to finished, and I'm getting samples of all the parts and the board from the company in China doing the sourcing, kitting, and direct fulfillment.  More updates at the end of the week, or early next week.

Re: Controller Board for Adafruit's Large RGB Matrix Display

Reply #50 –
Wow, I'm surprised it's been two weeks since my last update.  I ordered 100 boards from one of the prototyping PCB services in China, and was not happy with the results.  The silkscreen was not very sharp, which is just a cosmetic issue but I want my customers to receive good quality parts.  More troubling was solder mask that was far away from the pads.

I assembled several boards, and one board had a short from power to ground, which I traced back to a solder bridge between a pad on the power connector and the ground plane surrounding the pad, which was barely exposed by the solder mask.  I made the mistake of leaving the default Isolate=0 parameter for the ground plane, which put the ground plane 6 mils away from the pads.  With my OSH Park boards this was not an issue, but with the sloppy solder mask, there was a a decent amount of exposed ground plane.

I made some board revisions, giving the ground plane a 12 mil isolation and also setting the DRC to a 9 mil minimum spacing for all features to give a little more cushion for fabrication errors.  I switched vendors for my next order of boards, going with HQPCB, a vendor I used last time I was in Shenzhen thanks to some Makers who posted instructions online:
http://http://www.transfabric.org/where-pcbs-are-made/
http://http://tempeto.com/?p=1

The HQPCB boards were finished yesterday and I have samples on their way via DHL.  Hopefully these boards will have no issues and I'll be able to have the kits assembled and ready to ship.
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Re: Controller Board for Adafruit's Large RGB Matrix Display

Reply #51 –
Thanks for the update and the links to the blog articles - great reading!

Are the PCBs in the photo from the first batch or from the HQPCB batch? The quality (at least in the photo) seemed nice enough.

Did you use Google Translate to communicate with HQPCB or was it done in English or Chinese? Did you go for HQPCB due to the quality and/or pricing? I hadn't heard about them before but it seems like they are a nice PCB fab.

Re: Controller Board for Adafruit's Large RGB Matrix Display

Reply #52 –
The photos are from the HQPCB batch, I'm happy with the quality at least from the pictures.  I went with HQPCB first for the quick turnaround and ease of ordering without knowing Chinese.  I was getting boards in 48 hours for a reasonable price when I was in Shenzhen and needed to turn over prototypes quickly.  I ordered from them this time as I knew they had good quality at a reasonable price.

I used a combination of Google Translate and advice from those links I posted to order from HQPCB.  I could not figure out how to pay them myself without a Chinese bank account.  If I recall there used to be a way to add money to an Alipay account without having a Chinese bank account, but that didn't work when I tried (last year).  For this order I had a Chinese contact pay for me.

Re: Controller Board for Adafruit's Large RGB Matrix Display

Reply #53 –
Holy cow, this looks AWESOME.

I am eagerly awaiting the day when I can order one of these suckers. I've bumped up against the limits of the poor Atmega328....

If you have a working prototype, even if it's cosmetically imperfect, I will happily pay $$ to buy it from you ;)

Re: Controller Board for Adafruit's Large RGB Matrix Display

Reply #54 –
Any idea when you will make your software generally available. I've now collected all of my parts and just need the software to bring my project together.

Thanks in advance for all of your efforts.

Re: Controller Board for Adafruit's Large RGB Matrix Display

Reply #55 –
Hi Craig,

Email me (put together the words in my signature), and I'll put you on the beta list.  I'll make the software generally available after I have a few people run through the next release.

Re: Controller Board for Adafruit's Large RGB Matrix Display

Reply #56 –
I can't wait.. Great little project Louis!! I sent emails yesterday, and will wait for the release announcement!!

Re: Controller Board for Adafruit's Large RGB Matrix Display

Reply #57 –
I'm very glad I found this thread.  I'll be ordering a board when they're ready!

Re: Controller Board for Adafruit's Large RGB Matrix Display

Reply #58 –
Long time, no update...  I've been in China for the last two weeks, attending Ian's Hacker Camp, and meeting with partners for getting this kit made and distributed.  Good news is, the first 100 kits are all made, and are sitting with a company that will do order fulfillment.  I still need a few days to finish up travel and get back to a place that has decent internet so I can put a shopping cart up on the web and start taking orders.  I'll be putting up the board design and library source at the same time.

Re: Controller Board for Adafruit's Large RGB Matrix Display

Reply #59 –
Yeah!!!! Great work Louis!!