Check the eblock cables.
nothing 
don’t work
Have you tried to wire the TX to the RX pin on serial to USB converter, and then see if you access the serial port using a terminal program on the PC. You should be able to get an echo to chars typed into the terminal program.
for debug i try all the time with tx ->rx, right?
We need to isolate where the problem is located. I suggested you put the serial to USB converter into loopback and see if you are getting an echo from a terminal program.
ok, i plug tx on rx of usb converter, and i open the com2 with tera term.
no echo
the usb converter don’t need a power?
No it doesn’t need power. For some reasons I am thinking it is not COM2 on your PC
What other COM posts you have available/?
mmm
now, in echo server with panda2, i can’t write over serial port from pc to panda2, i can only read from tera term
the problem is located on tx on usb converter
how did you chech the cables?
yes i change 3 cables
I bought a new one
Open that virtual COM port using TeraTerm and connect the Tx to the Rx of the USB-to-Serial eblock (loopback connection). Then try to send some characters , the character should echo back to you.
@ Joe
See #22 
Thank you Mike for your time