I am working on an embedded system that is connected over USB serial TTY (i.e. /dev/ttyUSB0), which needs to interpret arrow keys sent via a virtual terminal such as screen. The problem is, the shell (bash) and or screen seems to digest the escape sequence and then send on just the last byte. So, taking the up-arrow key for example – 33[A (or ESC followed by [A), my embedded system on the other end of the serial terminal only receives A. Interestingly, or perhaps expectedly, a terminal emulator like TeraTerm under Windows has no issue passing on arrow keys to the same USB-connected hardware.
The behavior makes sense, I think; the terminal/shell needs to read the control characters, but is there any way to pass the sequences on untouched through serial without some kind of keyboard gymnastics or special program? I’d like to be able to do this on any system without any special extra software and using basic utilities.