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Altera_Forum's avatar
Altera_Forum
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15 years ago

multiprocessor and mutex question

Hi, My design contain two CPU's. Each have his own on-chip-RAM. My question is: If I want that CPU1 could read the CPU2's RAM, do I need to use mutex? Thanks.
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
14 years ago

It depends on the application. If you only need to read one word (32 bits) then you don't need a mutex. If you need to read a whole block made of several words, and need that block to be consistent, then you need a mutex. Without the mutex, if CPU1 is writing the block while CPU2 is reading it, then the CPU2 will get a mix of the old and the new block, which may have some undesirable consequences.