Hello guys, just wondering if there is a bare bone/stand alone design that fitted original pin layout used by shields.......dose that make seance???
Kind of a hybrid between this style of single sided BBB
But with this standardised pin map
Guess it could be done quite simply in eagle (by someone who knows ho to use Eagle much better then me!) by stripping the Arduino Single-Sided Serial version of its Serial based components and adjusting the ISP to a more assessable and suited to a TTL-RS232 Adapter?
I think you underestimate the "difficulty" of moving connectors around on a PCB. You might think that "gee, the Really Bare Bones Arduino fits on that 76mm*18mm PCB, if all you're doing is adding connectors in the right places, it ought to be trivial to fit it in the 70x55mm space of a "real" arduino." But the RBBB uses a "convenient" pinout, and "translating" pinouts is one of the more difficult and space-consuming things to do on a PCB, especially if its single sided...
But the SS v0.93W is still a improvement from the rev3 SS arduino though? (size wise)
Do you have a pdf transfer, or even better Eagle files still for the SS v0.93W above, as I would love to build that one along with the Serial SS v0.9W that you were king enough to post files for.
alsooooooo.... :
Is there more to come from the Shield-Duino, looks like such a interesting project? (Any chance of the Eagle files?)
Here's an outline comparison. The V.3 board adds another 10mm in the X direction and a bit in the Y direction, but it also moves the ICSP connector to the right place, adds auto-reset, the two extra pins on the power connect area, and some useful option jumpers and has fewer signal jumpers.
I'll check on the "publishable" status of the .93 version...
I've been working on a design and made two blog posts so far on the subject (which I'm calling "minimalduino"), with snapshots of one- and two-sided layouts I'm toying with. The single sided layout doesn't have the ISP header so it wouldn't really be shield-compatible, which is my goal.
I etched the 2-sided board (more as a 2-sided etching experiment than anything else) and assembled it with the minimal components. There are a few mistakes in the board though, the biggie being that DTS (or is it RTS?) doesn't work, so it won't accept a program via the FTDI cable header. (I also don't have enough caps for the 7805, and I incorrectly laid out the ISP header with two pins wired to SCK instead of one to SCK and one to MOSI, though that's fixed with a jumper in the board I built). I'll post EAGLE files this weekend and see if anybody can spot my boneheaded move.
The tricky parts about a single-sided design are routing pins D8-D13, the ISP header, and reset. Omitting unnecessary stuff like LEDs and voltage regulation make everything easier, but it's still a very tight fit as westfw pointed out. That angled ATmega might free up enough space though...
I built out the .61 version (minimalDuino61.sch) without the voltage regulation, but it won't allow me to upload... I think I may have messed up the 2-sided etch, even though I've tested every trace for continuity and bridges to neighbors... I wonder if anybody sees anything wrong with the schematic or with the board layout: minimalDuino61.brd?
I also uploaded a newer layout (sch, brd), laid out as a 1-sided board with more jumper traces (12) than I'd like. Here's a snapshot jpg. I think I'll move the ATmega over a bit and rework the lower right to see if I can reduce the number of jumpers.
The single sided board you posted the .jpg of is acutally quite nice, but I think there is a design flaw. The pin in the power header next to the reset pin is 5V on yours, where as it is 3.3V on "official" arduinos.
This could be less than desireable if a shield was expecting 3.3V on this pin
I think you should either leave this pin unconnected, or provide a 3.3V regulator on the board to provide this pin with the expected voltage. There is plenty of room for it , and you could at least provide the holes for it, you wouldn't HAVE to populate it if you know you aren't going to use it.
Nice work though - I'll definitely be considering making one.
Oh and also I'd change the diameter of the "vias" you will be using to solder in the jumpers - they are way too small to be drilled and soldered by hand. You can use the "change" tool to change the shape and diameter.
Almost forgot-- I wired the 3.3V pin to 5V early on after reading this thread about the 3.3V pin only providing up to 50mA...
Looking for shields that use 3.3V, I only found ones that have their own 3.3V regulators, and the USB host shield which is made for a 3.3V Arduino... but protoshield users would have trouble with the 3.3V pin providing 5V!
You're absolutely right-- there's room, so I'll add a TO-92 3.3V regulator and maybe another solder jumper if people want to short it to 5V. I'll post the next rev in a few days.
I uploaded my latest revision to a shared folder [new uload 1/22].
As Trialex suggested, I added a 3.3v regulator (mcp1700-330) and caps, and also made the jumper pads/vias and their holes bigger. Along the way I also noticed that I hadn't routed the input power to the "Vin" or "9V" pin, so that's fixed too.
I tried different main chip orientations, and followed westfw's example of rotating it 45 degrees-- gave plenty of room for power regulation in the lower left.
I'm not too happy with the power jumpers under the chip socket, but it should work OK and not be too tough to build out. And there are still more jumpers than I'd like, but since not everyone will need the ICSP (or is it just ISP?) header, it might not a big deal.
I'm curious if anybody would mind looking over the schematic for any errors or glaring omissions? I'll breadboard it in the coming week and try to get a sketch uploaded, but would appreciate any tips!
Key features:
(almost) everything optional,
barrel jack, .1" pin headers, or screw terminals for power input,
solder jumpers to bypass the diode and voltage regulator,
pin jumper to bypass the voltage regulator,
fourth standoff mounting hole for stability,
grounded hole for mounting a resonator instead of a crystal and caps.
Thanks for this salsaman, but seem to have a little trouble with the links
just get "Sorry, the page (or document) you have requested is not available." :-[
Thanks for the heads up! Not sure what happened there, but I made new folders and moved the files, replacing the links in yesterday's post with a single link to the new "minimalDuino75" folder with brd, sch, and jpeg snapshots. Should be good to go now!
I can't edit my previous post with the links to the .61 and .71 files, but there's a new shared folder for them.
I'll be careful with Google Docs shared folders from now on, and just make new ones when I have more to share...
Yellow boxes in the schematic are optional parts, with the ones in dotted line boxes meaning "at least one," since you could pick either (or both) programming header(s), any of the power jacks, and either a top or side reset button.
Jumper-wise, the one under the chip socket shouldn't be tough-- easy to run it under or to file a groove in the bottom of the socket. If the user doesn't need the ICSP header, the four jumpers on the right would not be needed, and the two (TX/RX) jumpers wouldn't be needed if not using the FTDI cable header.
Does it make any sense to have a jumper for the 5V regulator? I thought it might be useful to have a bypass if somebody installs the voltage regulator but then doesn't need it. Otherwise I think solder jumpers make sense for diode or voltage regulator bypassing, but I'm open to suggestions!
I haven't worked out all the numbers, but I'm testing a one-off board and it works great. I'm thinking about a PCB run from Gold Phoenix-- should be able to get 27 boards if I'm doing the math right, the PCBs should cost <$5, rectangular (not routed), 2-sided with the ROHS silver option, plus no jumpers needed.. Populating it (minimally) would cost somebody ~$7 more. If a dozen people show interest, I'll make the order for the PCBs-- anybody in? It would only need minimal edits to pass DRC I think.
BTW many thanks to wesfw-- that 1-sided serial board design was very helpful! And of course I'll add credits on the screen layer for the Arduino creators and westfw if I make an order...
i totally agree with westfw what you posted at the moment is a bare bones board that uses minimal space hence the corresponding connectors are placed in such a manner that they are at shortest distance to corresponding pins.now if you want to become a bit greedy and want to have same layout as before, you will have to sacrifice lot of component space compare to rbbb. but i guess the same pin mapping can be done on a double sided board with someone expert in eagle...
personally, if for home fabrication i wont mind playing around with the wires of shields rather than playing with a huge architecture of arduino's circuitry...
I wonder if anybody sees anything wrong with the schematic or with the board layout: 
