diff --git a/artiq/gateware/spi.py b/artiq/gateware/spi.py
index e476adbb9..b62782fbf 100644
--- a/artiq/gateware/spi.py
+++ b/artiq/gateware/spi.py
@@ -125,7 +125,7 @@ class SPIMachine(Module):
                     NextState("WAIT"),
                 )
             ).Else(
-                self.reg.shift.eq(1),
+                self.reg.shift.eq(~self.start),
                 NextState("SETUP"),
             )
         )