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Honored Contributor
Honored ContributorTristate bridge can't read data
I have a problem with a tristate bridge which intefaces between Nios and a few ram devices external to the sopc system. I can correctly write data to the devices but I can't read anything: reads a...
Altera_ForumHonored Contributor
Honored ContributorI eventually found the problem.
The hold time was nearly zero: when tristate bus deasserted rd signal the data was immediately removed from the bus; that's because the device was actually onchip ram and not a real tristate slave. Indeed the problem was triggered by the faster device: the previous one probably introduced a small hold time which has hidden the problem until now.
