This is the settings I'm using, checked that the drivers is installed and working and also that HEXminer is using correct rate.
Please correct the Serial Bitrate to 115200 then the miner will work.
Since my board work with 9600 so i forget this, sorry. Then change the baudrate on windows device manager to 115200 & select that too on HEX Miner.
Edit:
I just found out that baudrate can increase & decrease your hash rate. Try each baud rate to find best performance
115200 make my hash rate decrease.