Hi Stephane,

its stringend recommended to read the 8051 architecture description at first and then the P89C66x data sheet.

Only then you can see more clear, how the different memory areas of the 8051 family organized and why you must earn errors on ignoring its architecture.

Since the code, register, data, bdata, bit, idata, pdata, xdata areas are limited to different values and some areas overlap others.


Peter