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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
Icon for Honored Contributor rankHonored Contributor
16 years ago

Okay,

Here's what I found out!

When having a 16-bit device mapped to 32bit nios via tristate-bridge, every IOWR_16DIRECT will initiate 2 accesses to the device. Ex: IOWR_16DIRECT to 0x04 will write to location: 0x04 and 0x06.

My question is: is my observation true? Why is it designed that way? If it is that case, the CFI-flash will go crazy because all the command sequence will go wrong. I'm sure that someone already succeeded in getting the CFI flash working. How to work with CFI-flash ????

... Any reference design available?

Thanks a lot.

Jeff