the performance of NANO remains unchanged and the main control chip ATMEGA328P-AU remains unchanged, we replaced the USB chip to increase the download speed and increase the stability in win7 and win8.
Instructions:
1. Download uno's IDE
2. Download the USB chip driver
Download the CH340C driver
3. Plug in the NANO development board, the driver will be installed automatically
4. Select the board NANO in die
5. Select the COM port, this can be queried in my computer, the port in your uno development board just now