diff --git a/litex_boards/targets/digilent_nexys_video.py b/litex_boards/targets/digilent_nexys_video.py
index a3d0051..4370fb7 100755
--- a/litex_boards/targets/digilent_nexys_video.py
+++ b/litex_boards/targets/digilent_nexys_video.py
@@ -28,7 +28,7 @@ from liteeth.phy.s7rgmii import LiteEthPHYRGMII
 # CRG ----------------------------------------------------------------------------------------------
 
 class _CRG(Module):
-    def __init__(self, platform, sys_clk_freq, toolchain, with_video_pll=False):
+    def __init__(self, platform, sys_clk_freq, toolchain="vivado", with_video_pll=False):
         self.rst = Signal()
         self.clock_domains.cd_sys       = ClockDomain()
         self.clock_domains.cd_sys4x     = ClockDomain(reset_less=True)