diff --git a/artiq/gateware/eem.py b/artiq/gateware/eem.py
index 29ed3a330..203656638 100644
--- a/artiq/gateware/eem.py
+++ b/artiq/gateware/eem.py
@@ -431,7 +431,7 @@ class Grabber(_EEM):
         return ios
 
     @classmethod
-    def add_std(cls, target, eem, eem_aux=None, ttl_out_cls=None, iostandard="LVDS_25"):
+    def add_std(cls, target, eem, eem_aux=None, eem_aux2=None, ttl_out_cls=None, iostandard="LVDS_25"):
         cls.add_extension(target, eem, eem_aux, iostandard=iostandard)
 
         pads = target.platform.request("grabber{}_video".format(eem))
diff --git a/artiq/gateware/targets/kasli_generic.py b/artiq/gateware/targets/kasli_generic.py
index 6bf4c484c..87f511835 100755
--- a/artiq/gateware/targets/kasli_generic.py
+++ b/artiq/gateware/targets/kasli_generic.py
@@ -64,12 +64,17 @@ def peripheral_zotino(module, peripheral):
 
 def peripheral_grabber(module, peripheral):
     if len(peripheral["ports"]) == 1:
-        port, port_aux = peripheral["ports"][0], None
+        port = peripheral["ports"][0]
+        port_aux = None
+        port_aux2 = None
     elif len(peripheral["ports"]) == 2:
         port, port_aux = peripheral["ports"]
+        port_aux2 = None
+    elif len(peripheral["ports"]) == 3:
+        port, port_aux, port_aux2 = peripheral["ports"]
     else:
         raise ValueError("wrong number of ports")
-    eem.Grabber.add_std(module, port, port_aux)
+    eem.Grabber.add_std(module, port, port_aux, port_aux2)
 
 
 def add_peripherals(module, peripherals):