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Chapter 6: Solving Problems
If you're having problems with DMA
If you're having problems with DMA
Check to make sure that your external DMA process doesn't access memory ranges
mapped to emulation RAM (eram) or emulation ROM (erom). External DMA to
emulation memory resources is not supported.
If you're having problems with TPU
Motorola makes several versions of TPU microcode for certain 6833x
microprocessors. HP uses one of the versions in its 6833x emulators. If you are
using the default TPU functionality supplied by Motorola in the 6833x processor
you are emulating, and if the 6833x processor version in the emulator is different
from the 6833x processor version you are using in your target system, there may be
a mismatch in TPU functionality between the emulator and target TPU.
To overcome this problem, you can develop your desired functionality and load it
into on-chip RAM, and enable the TPU to use the code in RAM instead of the
default microcode supplied by Motorola.
At the end of your development process, use the emulator in the ACT mode to test
functionality of your target system. The ACT mode disables the emulation
processor and enables the target processor. In this mode, you can test to see if you
are obtaining the desired TPU functionality with your target TPU.
Note that when you reset the processor, the TPU reverts to use of the Motorola
TPU microcode instead of the code you have placed in on-chip RAM. When you
run performance verification within the emulator, any TPU code you have written
and loaded into RAM is lost. The performance verification procedure writes
special TPU code into on-chip RAM for use in testing the TPU.
Refer to the Motorola User's Manual for your MC6833x processor for information
about how to load microcode into on-chip RAM and how to enable the TPU.
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