Unit about communication with com1, com2

Hallo !

I have to write a program that communicates with com1 and com2.

Is there a unit that handles com1 and com2.

It should perhaps have a buffered sending and receiving of bytes, (or
characters or strings) and the ability to select communication
parameters (baud rate, parity and so on).

If someone could give me a hint where to get such a unit or even could
send me one (if it is shareware or freeware) I would be very happy.

Thanks in advance.

Bis auf ein ander Mal,  M.Weiss