Maybe it's a silly question, but why is it needed to have a USB converter? Specifically, in the article, they mention connecting to a raspberry Pi. Couldn't the

Maybe it's a silly question, but why is it needed to have a USB converter? Specifically, in the article, they mention connecting to a raspberry Pi. Couldn't they use the UART serial port on the GPIO of the Rpi? I see the baud rate seems limited to 4800, would that be the issue? (I don't know how this stuff work, I often use serial port to connect to my SBCs - RPi or similar - and I would love to use a minitel for that after reading the article ^^)