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Altera_Forum's avatar
Altera_Forum
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8 years ago

Signal Tap II reading a "1" from SO of FLASH CHIP always, without changes. why?

I'm creating a very simple Flash controller as a school project. The flash chip is MX25L3206E and the FPGA is 5CEFA4F23C8. I created the code attached and routed the proper pins from the chip. After ...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
8 years ago

SO idling HIGH wouldn't worry me. You may have a pull-up in the FPGA by default. Even if you don't I wouldn't be surprised if a tri-state line drifts up high, not low.

The Write Enable command is the only one I can think of that'll get you. You need it before you issue any command that can modify the contents of the FLASH - write, sector erase, bulk erase, write status, etc...

Cheers,

Alex