Von Neumann or Harvard?

classic Classic list List threaded Threaded
5 messages Options
Reply | Threaded
Open this post in threaded view
|  
Report Content as Inappropriate

Von Neumann or Harvard?

Lindy
The course material describe the HACK architecture as Von Neumann architecture with code (in ROM) and data (RAM) separated.  

Am I missing something?  I though that was the definition of Harvard architecture, when data and code are separate.  That is is more logical, and the reason I thought Von Neumann is more widely used is because back then it was cheaper.

Thanks!
Lindy
Reply | Threaded
Open this post in threaded view
|  
Report Content as Inappropriate

Re: Von Neumann or Harvard?

ybakos
It is indeed Harvard.
Reply | Threaded
Open this post in threaded view
|  
Report Content as Inappropriate

Re: Von Neumann or Harvard?

cadet1620
Administrator
In reply to this post by Lindy
"Von Neumann architecture" means different things in different academic cultures. See this post

--Mark.
Reply | Threaded
Open this post in threaded view
|  
Report Content as Inappropriate

Re: Von Neumann or Harvard?

Lindy
I didn't know it was that complicated.  :-)  I just assumed if code and data were together in the same memory, then Von Neumann.  If code and data were separate, you couldn't put code in the data part, and you couldn't put data in the code part, and the CPU was designed that way, then it is Harvard.

I've seen a couple of references to PIC's here.  I thing they are wonderful little machines.  That was my first experience with Harvard architecture.

I read your posts, though I don't quite see the differences, yet.

IBM's zSeries mainframe has special very fast data-only memory, sort of a little of both, I guess.

Lindy
Reply | Threaded
Open this post in threaded view
|  
Report Content as Inappropriate

Re: Von Neumann or Harvard?

Lindy
In reply to this post by cadet1620
Mark,

You wrote on your page: "The Hack computer is strictly Harvard architecture; the Program and Data Memories are completely independent and there is no data path between them."

Yet in chapter 5, page 79 it reads:
...section 5.1 gives a detailed description of the von Neumann architecture
—a central dogma in computer science underlying the design of almost all modern computers. The Hack platform is one example of a von Neumann machine, and section 5.2 gives its exact hard-
ware specification.

Anyway, when I read that I had to double check, so I ended up learning even more after all. :-)

Lindy
Loading...