Allow a counter to be manually reset

[nullobject]

• Depends on Allow a counter to be instantiated using a Scala range #1515.

This PR adds a reset parameter to the Counter API, that allows a counter to be reset to its initial value.

It is sometimes useful to be able to reset a counter arbitrarily. By default the reset parameter is false, which means the proposed change is compatible with the existing API.

For example

val counterReset = WireInit(false.B)
val (value, wrap) = Counter(0 to 3, reset = counterReset)

// Trigger a reset
counterReset := true.B

Type of change: other enhancement

Impact: API addition (no impact on existing code)

Development Phase: implementation

Release Notes
Allow counters to be reset

[seldridge]

With #1515 merged, would you be able to rebase this onto master @nullobject?

And thanks for this. It's something that I've written one-off workarounds on multiple occasions for.

[nullobject]

@seldridge Sure thing, I will get it out of draft status and mergable 👍

[nullobject]

With #1515 merged, would you be able to rebase this onto master @nullobject?

@seldridge It has been rebased.

[seldridge]

lgtm

I've wanted this for a while! Thanks for the contribution.

[seldridge]

This test is probably overkill and it seems to repeat (at least locally, for me) seeds. Out of scope for this PR, though. I like having this PR consistent with the other tests here.