Fix for Arbiter_Priority interrupting every grant at the next clock.

laforest / FPGADesignElements

A self-contained online book containing a library of FPGA design modules and related coding/design guides.

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Fix for Arbiter_Priority interrupting every grant at the next clock. #16

Closed BartHaagdorens closed 2 years ago

BartHaagdorens commented 2 years ago

Before the fix, Arbiter_Priority would only hold a granted request for one clock cyle and then interrupt it:

With no active requests, an all-zero grant is output (correct).
With a single active request , output alternates between granting the request and al all-zero grant.
With multiple active requests, output alternates between the two highest-priority requests.

With this fix, a granted request is held until the request is released.

laforest commented 2 years ago

Thank you for the insightful fix. I got cocky and didn't test enough this seemingly obvious code! I will look at it a bit more, as I'd rather not have requests be replaced by grant_previous in the masked request calculation.