I’ve been looking at what’s needed to “enable” the UART ports on the FEZ Panda as RS-232.
Not being an electrical engineer my first thought was to just wire the FEZ pins to a DB9 plug. I then realized the FEZ pins are 3.3V and RS-232 needs 5V.
I looked at the schematics for the EMX Development System and see that on the EMX board the UART pins are wired to a ST3222-TSSOP IC.
Is such an IC needed, what is it’s purpose?
Can that be done just using some capacitors, like here: http://www.watterott.com/de/RS232-Shifter-Board-Kit