thanks for ur response
in fact i want to design an interface.
by virtue of this interface i will get rid
of burning my programe into 8051 chip each time i want to test it
to imlement this first i will convert my hex file into bin file at pc end and then i will tranfer this bin file into the external code memory byte by byte.
at this point i am not clear what i should do because i am not clear what exacly bin file format is ???
wheather i have to trnsfer the bin file as a whole in external code memory or i have to trunk some header and trailer from it ?????