Q1. What's the difference between Arduino UNO and Seeeduino v4.2

Seeeduino v4.2 is fully compatible with Arduino UNO. The mainly difference list below:

* Use a micro USB to power and program the board

* 3 on-board Grove connector

* 3.3/5V system power switch

* DCDC circuit instead of LDO, more efficiency

* Others circuit improve

Q2. I can't upload my sketch to Seeeduino v4.2

* Check the Power LED on

* Choose the right Port and Board (Seeeduino v4.2)

* Close and reopen Arduino IDE and try again

Q3. Where can I find technical support if I have some other issue.

 Please send an email to techsupport@seeed.cc