Realtime Communication using RS232/UART

What is RS232/UART?

It's a way for 2 devices to transmit data betwen each other and has been around since 1960, It Can work over long disatnces but its slow even at short disatnces it only gets a few Kbps, It's fine for alot of uses like sending text

How to connect UART to 2 comptuers

Wire them up according to this diagram --make sure not to connect 10v rhs232 to the logic level 3v on something like a raspberry pi.

[]TX-----RX[]
[]GND---GND[]
[]RX-----TX[]

Communicate in Realtime with Minicom

Install Minicom & Lrzsz--Optional

Arch: pacman -S minicom lrzsz

Debian: apt install minicom lrzsz

Communicate

Run one of these on both devices

-D is for what UART device your using there's a few common ones here

minicom -D /dev/ttyUSB0
minicom -D /dev/ttyS0
minicom -D /dev/ttyACM0

once you in minicom press crtl+a e on both devies

now you should be able to type on one and see it on both device remember to press enter when you done typing as it not only indcates to the other user when your done typing but also allows them to type without is typeing over your pervious line

Sending files

With lrzsz installed with minicom you can send files by presing ctl+a s and use space to select files or enter Dirs you proabably want to make sure the files are quite small <1MB or you will be waiting a few hours to transfer the files, For Videos you can use ffmpeg to compress them down your probably going to want to go down to 320x180 depending on video, For Picutes you can just use gimp and reduse the qualty down to 1280x720 jpeg 60%.

Changing Boud Rate

You may also want to incrase the boud rate for faster file transfers or lower it for long distance's, to do that on both devices go into minicom and press crtl+a o find serial interface press e and change the boud rate to what ever you whant if you get messed up characters when typing then reduse the boud rate --Even a boudrate of 300 is still plenty fast for any but the fastest typers