diff --git a/Readme.md b/Readme.md
index 9b2bbae..5e938e9 100644
--- a/Readme.md
+++ b/Readme.md
@@ -84,6 +84,8 @@ sudo make -j12
    2. sudo ./install_drivers
    3. lsusb 检查安装的usb设备
    4. 重新拔插后显示  Bus 005 Device 011: ID 03fd:0008 Xilinx, Inc. Platform Cable USB II
+7. 配置Unused pin，避免报错 end of startup status: low
+   1. 在XDC文件里面添加 set_property BITSTREAM.CONFIG.UNUSEDPIN Pullup [current_design]
 
 ## tips