Rainbow Electronics T89C51CC02 - Manual (Page 19)

Rev.A - May 17, 2001 19
Preliminary
T89C51CC02
7.2.1.3. Hardware security space
The Hardware security space is a part of FM0 and has a size of 1 byte.
The 4 MSB can be read/written by software, the 4 LSB can only be read by software and written by hardware in
parallel mode.
7.2.1.4. Column latches
The column latches, also part of FM0, have a size of full page (128 bytes).
The column latches are the entrance buffers of the three previous memory locations (user array, XROW and
Hardware security byte).