diff --git a/cpu/mpc5xxx/usb.c b/cpu/mpc5xxx/usb.c
index 8f2b66a..bec7da3 100644
--- a/cpu/mpc5xxx/usb.c
+++ b/cpu/mpc5xxx/usb.c
@@ -32,9 +32,13 @@
 	/* Set the USB Clock						     */
 	*(vu_long *)MPC5XXX_CDM_48_FDC = CONFIG_USB_CLOCK;
 
+#ifdef CONFIG_PSC3_USB /* USB is using the alternate configuration */
+	/* remove all PSC3 USB bits first before ORing in ours */
+	*(vu_long *)MPC5XXX_GPS_PORT_CONFIG &= ~0x00804f00;
+#else
 	/* remove all USB bits first before ORing in ours */
 	*(vu_long *)MPC5XXX_GPS_PORT_CONFIG &= ~0x00807000;
-
+#endif
 	/* Activate USB port						     */
 	*(vu_long *)MPC5XXX_GPS_PORT_CONFIG |= CONFIG_USB_CONFIG;