diff --git a/README.MD b/README.MD
index 7f52082..0564730 100644
--- a/README.MD
+++ b/README.MD
@@ -16,6 +16,9 @@
 ## 3.Board choose
 - The board can choose `ESP32 Dev Module`, other settings can keep the default
 
+## 4. SD card connection
+- Demonstrate how to use the second SPI device, using the SD card as a demonstration device
+![](image/SD.jpg)
 
 ## Pinout
 | Name       | V18    |
diff --git a/image/SD.jpg b/image/SD.jpg
new file mode 100644
index 0000000..09f258c
Binary files /dev/null and b/image/SD.jpg differ