Thanks again for the comments.

Just to clarify, I don't wish to reverse engineer the software on the chip, I merely want to check its correct operation by means of a serial port.

I have several of these components and want to check to see if they still operate etc.

I guess what I'm looking for is a piece of software that would be able to display the output values etc from the 8052.
I just thought that underdstanding the original code would assist in this matter but do understand the legal implications.

If anyone could advise a good user freindly peice of software that would do this I would be most grateful.

Regards,
Stuart James