10Memory Interface
10 – 29
PMS = 1
PMS = 0
A13 = 0
A13 = 0
A13 = 1
A13 = 1PM Overlay 2
DM Overlay 1
DM Overlay 2
PM Overlay 1
There are some restrictions on using program memory overlays:
• The ADSP-2181’s program sequencer does not consider the value in the
PMOVLAY register. Switching pages during operations that are sensitive to
the current PMOVLAY register value can result in program execution errors.
For example, if your program is performing a loop operation on one of the
external overlays and the program changes to another external or internal
overlay, an incorrect loop operation could occur.
• The contents of the PMOVLAY register are not automatically saved and
restored on the processors status stack when the processor responds to an
interrupt. If your program uses overlays, you must save and restore the
Figure 10.27 Memory Overlay Addressing For Example Design
To Next Page
Loading...
Need help?
General
