Texas Instruments TMS320C80, User Manual

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Memory Differences
1-8 TMS320C80 to TMS320C82 Software Compatibility User’s Guide
1.5.2 Parameter RAMs
A parameter RAM is associated with each processor on a ’C8x
device. A portion of this RAM is dedicated to hardware parame-
ters, such as the state of suspended packet transfers, buffers for
external-to-external packet transfers, and interrupt vectors. The
remainder of each parameter RAM is available to software for
general-purpose data storage.
Figure 1–2 contrasts the memory maps for the on-chip parame-
ter RAM on the ’C80 and ’C82. All ’C80 memory locations occu-
pied by parameter RAM for PP0, PP1, and the MP are also popu-
lated on the ’C82. The memory locations occupied by the ’C80’s
parameter RAMs for PP2 and PP3 are unpopulated on the ’C82.
Each of the ’C82’s parameter RAMs is 4096 bytes long, which is
twice the size of each parameter RAM on the ’C80. The second
half of each of the corresponding memory spaces is unpopulated
on the ’C80.
Note:
In the ’C80, the MP parameter RAM can be accessed only by
the MP and TC. However, in the ’C82, the MP parameter RAM
can be accessed by the MP, TC, and PPs.