What does nios-run do?

[cruzin]

Hello,

I can download a program to memory using "nios-run my_prog.srec" and
it works fine.

However, when I write the program into the same memory manually (ie.
memory fill command), nios will not wrong the program properly.

I verified that both methods write exactly the same program bytes into
memory, but nios-run does something with the memory AFTER the program
end. This must be the source of my problems. Why are bytes changed
after the end of the program?

I verified every byte up until the last byte written as defined by the
S-Record.

Any ideas on what steps nios-run goes through?

Help is greatly appreciated.

 

[fabbl]

What are you talking about?

 

[Petter Gustad]

I can download a program to memory using "nios-run my_prog.srec" and
it works fine.

However, when I write the program into the same memory manually (ie.
memory fill command), nios will not wrong the program properly.

Maybe a stupid question: How do you run your manually entered program?
Are you using the go (G) command in germs? Can you use go to *re-run*
the downloaded srec file?

Petter

 

[cruzin]

Hi Petter,

I wrote a program to convert an Srec file to a binary file and then
downloaded this over a PCI/Avalon bridge.

I have found my problem, which was that I assumed the Srec file was
always writing a contiguous memory region, when in fact sometimes
addresses are skipped, presumably for alignment optimization.

 

[Nial Stewart]

Hi Petter,

I wrote a program to convert an Srec file to a binary file and then
downloaded this over a PCI/Avalon bridge.

I have found my problem, which was that I assumed the Srec file was
always writing a contiguous memory region, when in fact sometimes
addresses are skipped, presumably for alignment optimization.

If you have a look at the srec spec, I'm fairly sure the
first data after the 's' on every line is the address that
line starts at.


Nial

 

[cruzin]

Hi Nial,

Yes you are correct.

When I wrote my Srec-converter program, I looked at a nios-built Srec
file, and all records were contiguous. Later on, I realized in some
programs, nios-build will skip bytes here and there. Live and learn.