back.pysim: in simulator sync processes, start by waiting for a tick.

This matches Migen behavior and also makes more sense.

diff --git a/nmigen/back/pysim.py b/nmigen/back/pysim.py
index d09c981793f1da385c3bbfa10539e2b4205e98c6..ba4f0bcd7d9498c8be1b9cf033de913e7c6f57bc 100644 (file)
--- a/nmigen/back/pysim.py
+++ b/nmigen/back/pysim.py
@@ -241,7 +241,7 @@ class Simulator:
         process = self._check_process(process)
         def sync_process():
             try:
-                result = process.send(None)
+                result = None
                 while True:
                     if result is None:
                         result = Tick(domain)