I designed Skinny without really checking with people - that was my first mistake.
QuoteI designed Skinny without really checking with people - that was my first mistake.I think it's great that you built an Arduino variant outside the 'authorization process".
the 5v/3.3v shield thing is not a -huge- deal: avr's are (im like 99% sure) 5v compliant so, at worst, it should still work. (if using a r divider, then 1.8V is still higher than most CMOS Vih)
ironically, if you actually solder in female headers to put a shield on it, it will be exactly the same height as a diecimila
theres no 1k series resistor on RX0, which means if you've got a GPS (or xbee, or xport, etc) connected to rx/tx - many tutorials/examples do this - and the serial link installed (for debugging/uploading) its going to perform very strangely. if its not included, it should be noted
the switch would be 108914981273 times awesomer if it was RA and on the board edge so you could turn it on/off when a shield is on. no big deal tho. (i am rooting for a right angle 3pole switch in the next arduino rev.)
is the 3.3v on the serial connection an input (to VCCIO) or an output (from the internal miniregulator in the 'RL). if its the latter, thats kinda sketchy. :-/
the fuse seems a bit odd - the diecimila fuse is there to protect the computer's internal usb hub. a reasonable 3.3v regulator (you dont have the part number anywhere so i cant check it) should have short circuit protection.
i dont really get the 8mhz/'lilypad' thing. i use internal oscillators all the time for cheapie kits, but i'd never do it for a project where customers are expecting to use a serial library where they cant tweak the TCCR values (and where the bootloader is pre-burned with a set value that is not calibrated). i've found that the int oscillator does vary a bit over large runs/temp/voltage. why not include (at least) a ceramic oscillator? you can get a skinny one for $0.20, a full-on crystal setup is maybe $0.35 or $0.40
I don't really see any use for this. There several ways to interface an "normal" Arduino to 3.3V peripherals. And since they made a "full-sized" Arduino board anyway, why didn't they use the PDIP-Version of the chip (which can be replaced in case of an "accident").Eberhard
Quotethe 5v/3.3v shield thing is not a -huge- deal: avr's are (im like 99% sure) 5v compliant so, at worst, it should still work. (if using a r divider, then 1.8V is still higher than most CMOS Vih)Awesome feedback. Thanks! I am more worried about customers buying Skinny and getting frustrated when it doesn't work with their 5V XBee shield, etc. The ATmega168 should be able to clamp higher voltages without too many problems.
Quoteironically, if you actually solder in female headers to put a shield on it, it will be exactly the same height as a diecimila The power jack and USB connectors are pretty tall aren't they? And if we're going for pocket-ability, I'm thinking peeps will want to solder in their own wires.
The female connectors were a fantastic idea in the beginning. You ever try to desolder a through hold connector like that?
Quoteis the 3.3v on the serial connection an input (to VCCIO) or an output (from the internal miniregulator in the 'RL). if its the latter, thats kinda sketchy. :-/My designs are always a little sketchy If it sparks, unplug it. If it heats up, you better check VCC/GND. No really - The 3.3V pin on the male header on skinny is an input. The USB board provides 3.3V. You can have the board 'on' and hook up USB without problems. It's a little sketchy to have two vregs on the 3.3V bus at the same time, but both the FTDI vreg and the on-board SOT-23 mini vreg are both pretty burly when it comes to abuse (misuse).
Finally since this seems to be about options, I would add 2 pins at .1" spacing for + and - at the power connector to allow for some male pin headers to be soldered by the user instead of a barrel connector. This could be under the barrel connector or to its side somehow. If done well, the large holes for the bigger connector could be used as strain relief if soldering in wires.