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Re: PowerPC hangs on memory read


Andrew:

> You you checked the MMU setup? Maybe you don't have 
> access to this location?

I had a hunch it was MMU, but I was under the mistaken
impression that when enabled, the MMU was mapped to a 1:1
correspondence between logical and physical address 
_for_the_whole_extent_of_the_memory_ (this is not as
wasteful as it sounds since all the addressable space can 
be covered with large memory blocks resulting in acceptably
sized translation tables).

Obviously I was wrong, because once I recompiled Ecos
to disabled the MMU, everything works alright.

I peeked around, and I found one particularly interesting
function in the HAL, cyg_hal_map_memory(). Can
this function be called at any time or is it a setup only
call? In other words, can you augment the MMU translation
table at any time?

Thanks for your help!
Tony


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