Datasheet

Near Digital #10

CS - this is the Chip Select pin for the SD card. If you need to cut the trace to pin 10

because it is conflicting, this pad can be soldered to any digital pin and the software

re-uploaded

Near Digital #3 and #4

L2 and L1 - these are optional user-LEDs. Connect to any digital pin, pull high to turn

on the corresponding LED. The LEDs already have 470 ohm resistors in series.