So can someone tell me if this has anything wrong with it ?
Should be good ?
Why are you doing this?
Mostly just to learn, and should be cheaper. than buying a bunch of zeros.
i have a i2c screen and some knobs and buttons on a mcp io expander.
- Let’s see, you have copied an existing schematic and now want us to check if you copied it correctly ?
1 Like
yes Larry. thank you.
Hi, @mitcfew
Why do you have this;
Just a series protection diode instead of U10 will work with less volt drop.
Also U10 is providing a voltage difference in USB gnd and your controller gnd, may cause some problems.
Tom.... 
PS.SORRY, just saw the original schematic.. so you would not know. Looks like D+ and D- protection.
A distinct advantage to drawing ALL your wiring.
I think Vddin needs bypass cap(s)
Also, since the SAMD chips don’t use spi for programming, you should probably put some connector on the SWD and SWC pins.
I2C pullup resistors look rather strong.
(if the OP is still there)
Thank you for helping 
i figured that out after ordering
Version 2 works now tho
This topic was automatically closed 180 days after the last reply. New replies are no longer allowed.