From da76ffa781a4cce142c42f4f84fdaa4ae4758370 Mon Sep 17 00:00:00 2001 From: whitequark Date: Mon, 27 Apr 2020 02:06:10 +0000 Subject: [PATCH] lib.cdc: add missing documentation for AsyncFFSynchronizer. NFC. --- nmigen/lib/cdc.py | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/nmigen/lib/cdc.py b/nmigen/lib/cdc.py index 09cdd95..79cf1b2 100644 --- a/nmigen/lib/cdc.py +++ b/nmigen/lib/cdc.py @@ -116,6 +116,14 @@ class AsyncFFSynchronizer(Elaboratable): with higher numbers reducing MTBF further, at the cost of increased deassertion latency. async_edge : str The edge of the input signal which causes the output to be set. Must be one of "pos" or "neg". + max_input_delay : None or float + Maximum delay from the input signal's clock to the first synchronization stage, in seconds. + If specified and the platform does not support it, elaboration will fail. + + Platform override + ----------------- + Define the ``get_async_ff_sync`` platform method to override the implementation of + :class:`AsyncFFSynchronizer`, e.g. to instantiate library cells directly. """ def __init__(self, i, o, *, domain="sync", stages=2, async_edge="pos", max_input_delay=None): _check_stages(stages) -- 2.30.2