>Can I just replace the max 232 with another ic and go USB?
>If yes, what IC ?

The FTDI232B seems to be the highest regarded chip for doing USB to serial
conversion. List member Wouter sells them including as a conversion board,
but if you are wishing to connect between existing buts of equipment then
just getting a serial-USB cable may well be the way to go. Again Wouter has
the cables, but I do not know if his are specifically the FTDI chip version.
In the USA you may wish to look at http://www.rr-cirkits.com/ who sells a
USB-serial cable which I believe is an FTDI one.

Note that whatever you do, it is not just a "drop a different chip in" to
get USB. The chips have different pin outs and totally different packages to
the MAX232 chips. All the USB chips are surface mount.

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