--- Erik

>PS Why do you put code in RAM? the '51 is Harvard and made for code in ROM. For the ISP flash versions of the '51 such as P89c51Rx2 and P89C66x all you need to put code in is provided, working, for free.

Yes, i should have used P89c51RD2 instead, but i found it too 'difficult' for me for the 'first time'(i'm doing my first project).
Maybe i've rushed, but now no way back.

--- Michael

I think i'll manage without converting.
Anyway, thanks.

Thank you all,
Tom