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Altera_Forum
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18 years ago

Running into infinite loop problems

I'm relatively new to Quartus and I'm trying to define a latch with three outputs and the following properties: L M | Q(t+1) | R(t+1) | S(t+1) ------------------------------ 0 0 | S(t) ...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
18 years ago

If you really do need an unclocked latch, refer to the coding styles in the Quartus handbook that rmorley pointed you to. The chapter includes information on how to code latches to get a hazard-free implementation and where to look in the Analysis & Synthesis compilation report to confirm that you did indeed get that kind of implementation. If a latch is not listed as free of timing hazards, then it can do strange things in simulation and in real hardware. It could have glitches, wind up at the wrong level, or even oscillate continuously.