An "Empty place" is just that, a part footprint not populated it can be a by-pass, sometimes a jumper but mostly for the capacitors you MIGHT need... Possibly. Don't be stingy on by-pass caps. They are like "Magic Bullets" for weird problems AND you don't "Have" to use the pads and they are virtually free.Finally "Hangies" are the parts added, usually "Hanging" in air. I've done my share... cuts and jumpers... Toowith kynar wire-wrap wire... make the insulation the same color as the solder mask and that way the "Changes" can become 'nearly' invisible.Bob
Sorry, I meant to look at those files but forgot.The schematic is too hard to check properly without spending ages matching pin numbers so I'll give that a miss.Your general board layout looks good, tracks are at strange angles though but that's mostly an aesthetic thing.I'm not that experienced with laying out high-speed traces but the USB lines are supposed to be of equal length and IIRC impedance matched to 50R. I may be wrong and I have in fact had boards work without much care taken with the D+ and D- signals using an FTDI chip. But I think that chip is just low speed USB, the SAM does high-speed as well doesn't it?Your lengths look reasonable, but you have sharp corners and vias, all of which are bad for high speed signals. If you look at the Due traces they are matched,all on the top layer and no vias. Like I said though I don't now how important it is.So I'll be interested to see if the USB works, especially through all the connectors.Also I can't find R7 and R8 on the PCB. Can you post the Eagle design file? ______Rob
Good job sticking with the project until you got it working!
Yes well done and thanks for persevering with this.It will be interesting to see what the absolute bare minimum is so let us know if you do that.______Rob
So, thats how my "minimum" looks like. Well, thats all I need. I wont be frugal with the capacitors and hope this works Sorry for the wrong symbol of the switch (Schalter), but Multisim/Ultiboard doesnt allow different footprints for buttons :-/
Looks good. A lot more capacitors than I anticipated, and I wasn't sure if both crystals were necessary myself.So what's the programming process w/ the USB attached directly to the MCU? Erase program w/ the button, then hit reset and upload via arduino user interface or what? Can you just upload a hex file with another program instead?