diff --git a/examples/himbaechel/tangnano9k.cst b/examples/himbaechel/tangnano9k.cst
index a5d1610..6f5a33b 100644
--- a/examples/himbaechel/tangnano9k.cst
+++ b/examples/himbaechel/tangnano9k.cst
@@ -16,9 +16,10 @@ IO_LOC "LED_R" 10;
 IO_LOC "LED_G" 11;
 IO_LOC "LED_B" 13;
 
-IO_LOC "TXD" 32;
+// Use buildin USB-serial
+IO_LOC "TXD" 17;
 IO_PORT "TXD" PULL_MODE=UP;
-IO_LOC "RXD" 31;
+IO_LOC "RXD" 18;
 IO_PORT "RXD" PULL_MODE=UP;
 
 // fake
@@ -93,4 +94,4 @@ IO_PORT "tmds_clk_n" PULL_MODE=NONE DRIVE=8;
 
 INS_LOC "clk_div" TOPSIDE[0]; 
 
-IO_LOC "div_led" 10;
\ No newline at end of file
+IO_LOC "div_led" 10;