Opinions Requested - Small Propeller (P8X32A-D40) prototyping board idea
Wossname
Posts: 174
As part of learning the DipTrace suite of software, I decided to design a small, convenient PCB layout for a Propeller prototyping board, analogous to the Arduino board except with off-board FTDI (via the Prop Plug or similar).
I've finished the initial design - the schematic is basically just the one from the Propeller manual, but also has a 3v3 voltage regulator circuit on the board too.
My question is this: Is it worth me doing anything with this design such as making it open source under the Creative Commons licence (Github was suggested to me as a means of distributing it)? Would anyone be interested in such a thing or is it a bit pointless?
I only did it for a bit of fun but I did build a perfboard version of it and I use it quite a lot. The Layout for the proper PCB design is 1.65" x 2.575" - so it's substantially smaller than the Arduino and it's all SMD components apart from the Propeller PDIP chip itself, which is mounted in a socket.
It's not particularly technically accomplished or anything (it's only a 2 layer board), it didn't take long to create but perhaps someone would find such a thing useful.
I still have a bit of cost optimising to do but I reckon this design could be built (think PCB Cart or similar fabrication company) and populated for less than $16 including the Propeller chip.
So yeah, I'd like to know what people think of this idea.
I've finished the initial design - the schematic is basically just the one from the Propeller manual, but also has a 3v3 voltage regulator circuit on the board too.
My question is this: Is it worth me doing anything with this design such as making it open source under the Creative Commons licence (Github was suggested to me as a means of distributing it)? Would anyone be interested in such a thing or is it a bit pointless?
I only did it for a bit of fun but I did build a perfboard version of it and I use it quite a lot. The Layout for the proper PCB design is 1.65" x 2.575" - so it's substantially smaller than the Arduino and it's all SMD components apart from the Propeller PDIP chip itself, which is mounted in a socket.
It's not particularly technically accomplished or anything (it's only a 2 layer board), it didn't take long to create but perhaps someone would find such a thing useful.
I still have a bit of cost optimising to do but I reckon this design could be built (think PCB Cart or similar fabrication company) and populated for less than $16 including the Propeller chip.
So yeah, I'd like to know what people think of this idea.
Comments
I'd post it, it looks quite neat and someone might want to get it made.
It's a small world - I've already been reading your blog and +1'ing your posts on it :-)
I would love to see your design. Right now I'm doing the exact same thing with a view to turning it into a hackerspace business card. Did you go through-hole or smt?
I publish my designs on github here: http://github.com/redvers/isokeyboard
I'll try to get it uploaded to github later on then. What format should I upload? I'll put the Diptrace files on there of course but should I also add the Gerbers and bill of materials?
I've not generated Gerber output before so someone will have to let me know if I've done it wrong
I'll drop a link on here when it's up, thanks for the input guys.
The Propeller seems to have a pretty friendly community grown up around it. Much more so, I'd say, than the Arduino. Long may it remain
Yes, welcome to the forums.
I also like your Propeller board.
I know you said you followed the schematics in the manual but one thing I've read many times on this forum is that there should be a 0.1uF decoupling capacitor very close to each Vdd pin on the Prop. Apparently these caps are even more important if one overclocks their Prop but even at 80MHz they are strongly recommended.
As usual, the more Propeller board options, the merrier.
It would also be a good idea to have the other forum members take a look at the copper layers of your board. There are several members with a lot of circuit board designing experience here.
Duane
It's funny because this is the exact thing that excites me about the propeller community so much more than the Arduino community. The two schools of thought:
- A single physical design that everyone can interface to and builds "shields" for.
- A plethora of designs from which to choose from with a community willing to help you roll your own.
It reminds me of the philosophical discussion I see in the Open Source Software community where people consider code-forking to be disrespectful or harmful. It really isn't. It's a wonderful thing because with forking we get diversity, choice and competition.The problem with "standard" designs is that they quickly become straight-jackets.
I'd love to have some experienced board designers give me some tips on how the design can be tidied up, I'm sure I've made a whole raft of newbie errors. I didn't put any decoupling caps in this first spin, but I'll put it on the wish list for the next revision.
Anyway, I've released "Protopeller" (as I'm calling it, can't believe that name wasn't taken already!) in it's design form here:
http://github.com/AdamWard/Protopeller
It's under the CC-BY-SA 3.0 licence, so it's nice and easy to play with
I welcome any and all creative criticism and I will be glad to credit anyone in the "credits" file in the main repo.
I'm planning to figure out alternative file types that I can add to this repo - I appreciate that not every hobbyist can afford expensive tools like DipTrace - so it would be valuable to get this design exported into different formats such as Gerber, netlists, gcode and anything else that anyone wants. All suggestions welcome.
I don't use Diptrace, so I could be wrong, but the copper pour doesn't seem to be connected to ground.
It's not usual to use buses for supplies on schematics, just use short connections to a Vcc or Gnd symbol. I've attached one of my schematics.
I like "Protopeller." I wish I had thought of it.
Duane
DipTrace does have a free version and your design should easily fit within the requirements for the free version. However, exporting a clean set of gerber files would also allow anyone to have the board made by any fab shop and they won't have to even touch the design files.
Lastly, your perfboard version is fantastic! Excellent layout work.
@jonnymac: FYI, I am using 2.1.9.3 and it came right in.
I'm having the same problem as Jon. I'm using (2.1.9.0)
p.s., no you did not waste your money. You can upgrade to the latest version (2.1.9.5) for free and when 2.2 is released, all 2.x users get it for free as well.
I'm running BETA 2.1.9.0
@Leon / @WBAC: How come it's supposed to be a 5MHz crystal? Does that get multiplied up to 80Mhz internally?
@Publison: There's way less than 300 pins in this design.
It sucks that people can't open it, I'll try to do something about that. Stay tuned.