Parviz,

Please be patient. I have told you in other threads that I intend to "donate" source code for a program that does ISP for the 'S8252. It is easy to add support for the 'S53, since it uses the same 3-byte ISP instruction set. Today I will investigate adding support for the 'S51 and 'S52, which use a different 4-byte instruction set. I hope to announce availablility before Monday.

Now, whether or not you will be able to benefit from what I donate, is an entirely different matter!