Yes, it can be done. You will have to use the MSCOMM activex.

http://msdn.microsoft.com/en-us/library/aa259393(VS.60).aspx

I have not personally used MSCOMM to communicate with serial  devices from VBA (I
have done it with VB6). I did work on a project that communicated with GPIB and
Modbus devices, however. Getting the serial port  to work should be no problem.