What is the difference between MMU and MPU?

Do you have a question? Post it now! No Registration Necessary

Translate This Thread From English to

Threaded View
Guys,
I don't really know the difference between MMU and MPU. Could anyone
give me a brief idea about it?

Re: What is the difference between MMU and MPU?

Quoted text here. Click to load it

Whatsamatta you? Haven't figured out how to use Google to look
up answers to homework questions?

MMU == memory management unit

It's a part of a CPU (or an external peripheral) that handles
things like memory segmentation and protection, virtual memory
paging, etc.  Basically it sits between the CPU itself and
external memory and translates virtual memory addresses
produced by the CPU into physical memory addresses and raises
an exception when there isn't a valid mapping for the requested
operation and address.

MPU == micro processor unit

The rest is left as an exercise for the reader...

--
Grant Edwards                   grante             Yow!  I feel... JUGULAR...
                                  at              
We've slightly trimmed the long signature. Click to see the full one.
Re: What is the difference between MMU and MPU?
Quoted text here. Click to load it

;-)

Quoted text here. Click to load it

Sometime also

MPU == Memory Protection Unit

Handles only memory protection and often is limited to a few regions.

---
42Bastian
Do not email to snipped-for-privacy@yahoo.com, it's a spam-only account :-)
We've slightly trimmed the long signature. Click to see the full one.
Re: What is the difference between MMU and MPU?
Quoted text here. Click to load it

hi,

As far as i know, MMU are more complex than MPU.
MPU only offer access management over memory areas (depending on running
level, some may be set not accessible), whereas MMU enables you to create
virtual memory spaces.
With MMU the logical mapping differs from physical mapping, and depending on
the complexity of the MMU it may be possible to make a fragmented set of
memory chunk look like a continuous area, or do some swapping with mass
storage device. MMU also checks access stay within defined context limits.
The little drawbacks for MMU are quite bigger memory description tables and
maybe some increased access delay, power consumption and costs.

hope this will help!

PY



Re: What is the difference between MMU and MPU?

Quoted text here. Click to load it
I assumed you were talking about Memory units
I went across a MPU concept, as memory protection unit, while working on
secured microcontrollers for paycard systems

sorry if the real question was processing unit vs. memory unit.

PY



Re: What is the difference between MMU and MPU?

Quoted text here. Click to load it

Memory Protection Unit prevents a user application from accessing memory
regions own by OS.

Memory Management Unit can do the same thing, but it also provide
virtual memory (mapping of logical memory to a physical memory based on
memory base offset defined by OS).  In this way, a user program don't
have to be loaded into a fix location in the main memory.  It can be
loaded and execute from anyway in the system memory, and the MMU can do
the memory translation during program execution.

Joe




Site Timeline