diff --git a/scripts/ecc-heap.sh b/scripts/ecc-heap.sh
index 94a04cf..69777a6 100755
--- a/scripts/ecc-heap.sh
+++ b/scripts/ecc-heap.sh
@@ -59,8 +59,8 @@
 
 for F in 0 1; do
     for W in 2 3 4 5 6; do
-        scripts/config.pl set MBEDTLS_ECP_WINDOW_SIZE $W
-        scripts/config.pl set MBEDTLS_ECP_FIXED_POINT_OPTIM $F
+        scripts/config.py set MBEDTLS_ECP_WINDOW_SIZE $W
+        scripts/config.py set MBEDTLS_ECP_FIXED_POINT_OPTIM $F
         make benchmark >/dev/null 2>&1
         echo "fixed point optim = $F, max window size = $W"
         echo "--------------------------------------------"