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Altera_Forum
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13 years ago

Synthesis error in Quartus v12 & v11

There is an apparent synthesis error in Quartus v12, v11 and possibly other versions. I found this by adding an asynchronous preset to a register bit. When this is done that register bit is not prese...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
13 years ago

The problem should be expected to occur in a reduced design as well, did you try?

qCtrl[2] will be synthesized applying "not pushback", means the polarity of this register bit is inverted, also it's D and Q lines. As a side effect, the initial state of qCtrl[2] changes to '1'. Did you notice?