diff --git a/minitests/roi_harness/runme.sh b/minitests/roi_harness/runme.sh
index e6034ccc..8df1f02c 100755
--- a/minitests/roi_harness/runme.sh
+++ b/minitests/roi_harness/runme.sh
@@ -34,8 +34,8 @@ if [ "$SMALL" = Y ] ; then
 else
     echo "Design: large"
     export PITCH=2
-    export DIN_N=16
-    export DOUT_N=16
+    export DIN_N=17
+    export DOUT_N=17
     export XRAY_ROI=SLICE_X0Y100:SLICE_X35Y149
 fi
 
diff --git a/minitests/roi_harness/runme.tcl b/minitests/roi_harness/runme.tcl
index 42ff1423..c41c021c 100644
--- a/minitests/roi_harness/runme.tcl
+++ b/minitests/roi_harness/runme.tcl
@@ -160,8 +160,13 @@ if {$part eq "xc7a50tfgg484-1"} {
         # https://raw.githubusercontent.com/Digilent/digilent-xdc/master/Basys-3-Master.xdc
 
         # Slide switches
-        set sws "V17 V16 W16 W17 W15 V15 W14 W13 V2 T3 T2 R3 W2 U1 T1 R2"
-        set leds "U16 E19 U19 V19 W18 U15 U14 V14 V13 V3 W3 U3 P3 N3 P1 L1"
+        set ins "V17 V16 W16 W17 W15 V15 W14 W13 V2 T3 T2 R3 W2 U1 T1 R2"
+        set outs "U16 E19 U19 V19 W18 U15 U14 V14 V13 V3 W3 U3 P3 N3 P1 L1"
+
+        # UART
+        lappend ins B18
+        lappend outs A18
+
 
         # 100 MHz CLK onboard
         set pin "W5"
@@ -169,13 +174,13 @@ if {$part eq "xc7a50tfgg484-1"} {
 
         # DIN
         for {set i 0} {$i < $DIN_N} {incr i} {
-            set pin [lindex $sws $i]
+            set pin [lindex $ins $i]
             set net2pin(din[$i]) $pin
         }
 
         # DOUT
         for {set i 0} {$i < $DOUT_N} {incr i} {
-            set pin [lindex $leds $i]
+            set pin [lindex $outs $i]
             set net2pin(dout[$i]) $pin
        }
     } else {