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Altera_Forum
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12 years ago

Cyclone V: Communication with EPCQ Device in User Mode after Bootup

For my design, I'm using the Cyclone V (5CEFA7F23). I'm looking to boot the "factory image" from an EPCQ flash device using Active Serial x4, and then from the factory image (when in user mode), com...
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Altera_Forum
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12 years ago

I have recently been doing the same thing, and according to Altera it is not possible to use these pins directly in user mode.

However, the ALTASMI_PARALLEL IP can be used to access the flash.

In my opinion, ALTASMI_PARALLEL has a lot of weaknesses:

  • It does not have a working simulation model.

  • It is not well documented what is happening on the interface towards the flash.

  • We found a problem with the sector erase command (which is supposed to be fixed in 13.1)

For these reasons, we desided to make a new revision of the board and connect these pins in parallel to standard IO pins.

We then used our own hdl module to control the flash. This works perfectly, but you have to remember to check the "Enable input tri-state on active configuration pins in user mode"