Forum Discussion

Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
12 years ago

using epcs flash for both reset vector and store configuration

Hello all, I've tried to make a system in which the EPCS device would hold basically all information required for a working equipment. When implementing it, I couldn't open the EPCS device in N...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
12 years ago

You need to make sure that you are writing to a different flash sector from those that are loaded at boot time.

When I looked through the altera flash driver code it really wasn't the functions I was looking for!

The internal low-level functions might be useful, but the outer level ones the application is expected to use are hopeless.

Apart from all the extra layers of code, the big fubar is that it won't let you write to part of a flash sector without erasing the entire sector.

It really should allow the write if the old data is all 0xff (more particulary if the write only needs to clear bits), otherwise you need a 128k memory block to do your own RMW cycle. If you have to use internal memeory that is a lot of the devices memory.