The pit I walked through: the first ad Sketchpad

1. The screen print is too small , I can hardly see , The silk screen printing position is not well placed , Be overwritten .
2. When leading out the pin, you don't pay attention to whether its default function is IO mouth , As a result, a row of motor drive pins specially led out are all invalid .
3. 2401, Pin arrangement of Bluetooth module , Did not consider the actual placement , The physical objects are placed in conflict .
4. LED The lamp is not marked with positive or negative , Two rows of needles didn't look at the package , Turned out to be 1,3,5,7,9,2,4,6,8,10, Of .
5. The white board doesn't look good , Or black handsome .