Embedded Systems cover a vast spectrum from tiny microcontrollers to Windows & linux-based PCs
However, serial interfaces (“RS232”) must be one of the most common found in embedded systems of all shapes and sizes!
That depends on what, exactly, you mean by, “embedded system”
That depends on what bandwidth you require. The Product Technical Specification (PTS) will tell you the maximum serial port speed - you should be able to work from there…
Which firmware - the SL8082, or the “embedded system”?