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Altera_Forum's avatar
Altera_Forum
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16 years ago

double write pulse using only one single IOWR_16DIRECT

Hi, I've hooked up a CFI flash (8MB) to the Tristate bus. I've managed to get the CFI query working, however, I can't write to the flash at all. Observing the bus, I've found out that every IOW...
Altera_Forum's avatar
Altera_Forum
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16 years ago

You won't be able to program flash if there are any other cycles during the programming sequence.

So you must use cache bypass instructions.

Also you must stop any data in the cache being written back - eg by being displaced to make way for more data.

So you'll need to (at least partially) flush the data cache.

Also I believe you'll always see two cycles on a 16bit peripheral since the nios always does 32 bit cycles. I don't think the bus bridges supress the cycles which have no active byte enables.