If the firmware not reporting its version, you need to Enable UART in Configuration Files :
run " sudo nano /boot/config.txt " , add enable_uart=1 and reboot .
( If ttyS0 dosn't appear when running " sudo dmesg | grep tty " . Change the port to ttyAMA0 )
If the firmware not reporting its version, you need to Enable UART in Configuration Files : run " sudo nano /boot/config.txt " , add enable_uart=1 and reboot .
( If ttyS0 dosn't appear when running " sudo dmesg | grep tty " . Change the port to ttyAMA0 )