Hello. almost all computers that have a serial port have a UART that is actually 2 serial ports on one chip. The current generation of Mac laptops have an Intel motherboard and CPU. After doing Intel hardware research I discovered that the serial ports reported by windows are real. On the board is the industry standard mini connector so a little hack was the order of the day. Now there are 2 real 232/485 IO ports on the box, not some convoluted serial port solution.