diff --git a/1.54inch_e-paper_b_code/python2/epd1in54b.py b/1.54inch_e-paper_b_code/python2/epd1in54b.py
index c71af11..5e19094 100644
--- a/1.54inch_e-paper_b_code/python2/epd1in54b.py
+++ b/1.54inch_e-paper_b_code/python2/epd1in54b.py
@@ -98,6 +98,7 @@ class EPD:
         self.reset_pin = epdconfig.RST_PIN
         self.dc_pin = epdconfig.DC_PIN
         self.busy_pin = epdconfig.BUSY_PIN
+        self.cs_pin = epdconfig.CS_PIN
         self.width = EPD_WIDTH
         self.height = EPD_HEIGHT
 
@@ -151,12 +152,16 @@ class EPD:
         epdconfig.delay_ms(200)   
 
     def send_command(self, command):
-        epdconfig.digital_write(self.dc_pin, GPIO.LOW)
+        epdconfig.digital_write(self.cs_pin, GPIO.LOW)
+        epdconfig.digital_write(self.dc_pin, GPIO.HIGH)
         epdconfig.spi_writebyte([command])
+        epdconfig.digital_write(self.cs_pin, GPIO.HIGH)
 
     def send_data(self, data):
+        epdconfig.digital_write(self.cs_pin, GPIO.LOW)
         epdconfig.digital_write(self.dc_pin, GPIO.HIGH)
         epdconfig.spi_writebyte([data])
+        epdconfig.digital_write(self.cs_pin, GPIO.HIGH)
         
     def wait_until_idle(self):
         while(epdconfig.digital_read(self.busy_pin) == 0):      # 0: idle, 1: busy
diff --git a/1.54inch_e-paper_b_code/python3/epd1in54b.py b/1.54inch_e-paper_b_code/python3/epd1in54b.py
index 2309d7f..521f5d3 100644
--- a/1.54inch_e-paper_b_code/python3/epd1in54b.py
+++ b/1.54inch_e-paper_b_code/python3/epd1in54b.py
@@ -98,6 +98,7 @@ class EPD:
         self.reset_pin = epdconfig.RST_PIN
         self.dc_pin = epdconfig.DC_PIN
         self.busy_pin = epdconfig.BUSY_PIN
+        self.cs_pin = epdconfig.CS_PIN
         self.width = EPD_WIDTH
         self.height = EPD_HEIGHT
 
@@ -151,12 +152,16 @@ class EPD:
         epdconfig.delay_ms(200)   
 
     def send_command(self, command):
-        epdconfig.digital_write(self.dc_pin, GPIO.LOW)
+        epdconfig.digital_write(self.cs_pin, GPIO.LOW)
+        epdconfig.digital_write(self.dc_pin, GPIO.HIGH)
         epdconfig.spi_writebyte([command])
+        epdconfig.digital_write(self.cs_pin, GPIO.HIGH)
 
     def send_data(self, data):
+        epdconfig.digital_write(self.cs_pin, GPIO.LOW)
         epdconfig.digital_write(self.dc_pin, GPIO.HIGH)
         epdconfig.spi_writebyte([data])
+        epdconfig.digital_write(self.cs_pin, GPIO.HIGH)
         
     def wait_until_idle(self):
         while(epdconfig.digital_read(self.busy_pin) == 0):      # 0: idle, 1: busy
diff --git a/1.54inch_e-paper_c_code/python2/epd1in54.py b/1.54inch_e-paper_c_code/python2/epd1in54.py
index 3e45f38..c5907ca 100644
--- a/1.54inch_e-paper_c_code/python2/epd1in54.py
+++ b/1.54inch_e-paper_c_code/python2/epd1in54.py
@@ -82,6 +82,7 @@ class EPD:
         self.reset_pin = epdconfig.RST_PIN
         self.dc_pin = epdconfig.DC_PIN
         self.busy_pin = epdconfig.BUSY_PIN
+        self.cs_pin = epdconfig.CS_PIN
         self.width = EPD_WIDTH
         self.height = EPD_HEIGHT
 
diff --git a/2.13inch_e-paper_d_code/bcm2835/readme.txt b/2.13inch_e-paper_d_code/bcm2835/readme.txt
index b43b704..f660640 100644
--- a/2.13inch_e-paper_d_code/bcm2835/readme.txt
+++ b/2.13inch_e-paper_d_code/bcm2835/readme.txt
@@ -1,7 +1,7 @@
 /******************************************************************************
  * File Name          : readme.txt
  * Description        : Readme file
- * Date               : July-28-2017
+ * Date               : 2019-04-08
  ******************************************************************************
  *
  * Copyright (c) 2017 Waveshare
@@ -66,13 +66,24 @@
   * BUSY   ->    18 (Physical, BCM: 24)
 
   == How to use ==
-  1, install the C libraries of bcm2835, see: http://www.airspayce.com/mikem/bcm2835/
-  2, change the current directory to where the Makefile and demo files located.
-  3, compile the file with: 
-       make
-     If you need to see the debug information, clear the execution:
-     make DEBUG=-DDEBUG
-  4, run the demo with: 
+    1, open spidev.
+        spi is enabled in config.txt:
+        dtparam=spi=on
+    or in shell:
+        sudo raspi-config
+            - 5 Interfacing Options  Configure connections to peripherals
+                - 5 Interfacing Options  Configure connections to peripherals
+    
+    2, install the C libraries of bcm2835, see: http://www.airspayce.com/mikem/bcm2835/
+    
+    3, change the current directory to where the Makefile and demo files located.
+    
+    4, compile the file with: 
+        make
+    # If you need to see the debug information, clear the execution:
+        make DEBUG=-DDEBUG
+    
+    5, run the demo with: 
        sudo ./epd
   */
 
diff --git a/2.13inch_e-paper_d_code/python2/readme.txt b/2.13inch_e-paper_d_code/python2/readme.txt
index ffb8fc9..45151d8 100644
--- a/2.13inch_e-paper_d_code/python2/readme.txt
+++ b/2.13inch_e-paper_d_code/python2/readme.txt
@@ -1,7 +1,7 @@
 /******************************************************************************
  * File Name          : readme.txt
  * Description        : Readme file
- * Date               : July-28-2017
+ * Date               : 2019-04-08
  ******************************************************************************
  *
  * Copyright (c) 2017 Waveshare
@@ -66,12 +66,27 @@
   * D/C    ->    22 (Physical, BCM: 25)
   * RES    ->    11 (Physical, BCM: 17)
   * BUSY   ->    18 (Physical, BCM: 24)
+  
+    == How to use ==
+    1, open spidev.
+        spi is enabled in config.txt:
+        dtparam=spi=on
+    or in shell:
+        sudo raspi-config
+            - 5 Interfacing Options  Configure connections to peripherals
+                - 5 Interfacing Options  Configure connections to peripherals
+        
+    2, install the Python libraries.
+        sudo apt-get install python-pip 
+        sudo pip install RPi.GPIO
+        sudo pip install spidev
+        sudo apt-get install ttf-wqy-zenhei ttf-wqy-microhei
 
-  == How to use ==
-  1, install the Python libraries.
-  2, change the current directory to where the demo files located.
-  3, run the demo with: 
-     python main.py
+    3, change the current directory to where the demo files located.
 
-  */
+    4, run the demo with: 
+        sudo python main.py
+    # if use python3:
+        sudo python3 main.py
+*/
 
diff --git a/2.13inch_e-paper_d_code/python3/readme.txt b/2.13inch_e-paper_d_code/python3/readme.txt
index ffb8fc9..45151d8 100644
--- a/2.13inch_e-paper_d_code/python3/readme.txt
+++ b/2.13inch_e-paper_d_code/python3/readme.txt
@@ -1,7 +1,7 @@
 /******************************************************************************
  * File Name          : readme.txt
  * Description        : Readme file
- * Date               : July-28-2017
+ * Date               : 2019-04-08
  ******************************************************************************
  *
  * Copyright (c) 2017 Waveshare
@@ -66,12 +66,27 @@
   * D/C    ->    22 (Physical, BCM: 25)
   * RES    ->    11 (Physical, BCM: 17)
   * BUSY   ->    18 (Physical, BCM: 24)
+  
+    == How to use ==
+    1, open spidev.
+        spi is enabled in config.txt:
+        dtparam=spi=on
+    or in shell:
+        sudo raspi-config
+            - 5 Interfacing Options  Configure connections to peripherals
+                - 5 Interfacing Options  Configure connections to peripherals
+        
+    2, install the Python libraries.
+        sudo apt-get install python-pip 
+        sudo pip install RPi.GPIO
+        sudo pip install spidev
+        sudo apt-get install ttf-wqy-zenhei ttf-wqy-microhei
 
-  == How to use ==
-  1, install the Python libraries.
-  2, change the current directory to where the demo files located.
-  3, run the demo with: 
-     python main.py
+    3, change the current directory to where the demo files located.
 
-  */
+    4, run the demo with: 
+        sudo python main.py
+    # if use python3:
+        sudo python3 main.py
+*/
 
diff --git a/2.13inch_e-paper_d_code/wiringpi/readme.txt b/2.13inch_e-paper_d_code/wiringpi/readme.txt
index b43b704..78185dc 100644
--- a/2.13inch_e-paper_d_code/wiringpi/readme.txt
+++ b/2.13inch_e-paper_d_code/wiringpi/readme.txt
@@ -1,7 +1,7 @@
 /******************************************************************************
  * File Name          : readme.txt
  * Description        : Readme file
- * Date               : July-28-2017
+ * Date               : 2019-04-08
  ******************************************************************************
  *
  * Copyright (c) 2017 Waveshare
@@ -66,13 +66,28 @@
   * BUSY   ->    18 (Physical, BCM: 24)
 
   == How to use ==
-  1, install the C libraries of bcm2835, see: http://www.airspayce.com/mikem/bcm2835/
-  2, change the current directory to where the Makefile and demo files located.
-  3, compile the file with: 
+    1, open spidev.
+        spi is enabled in config.txt:
+        dtparam=spi=on
+    or in shell:
+        sudo raspi-config
+            - 5 Interfacing Options  Configure connections to peripherals
+                - 5 Interfacing Options  Configure connections to peripherals
+    
+    2, install the C libraries：
+        sudo apt-get install git
+        sudo git clone git://git.drogon.net/wiringPi
+        cd wiringPi
+        sudo ./build
+    
+    3, change the current directory to where the Makefile and demo files located.
+    
+    4, compile the file with: 
        make
-     If you need to see the debug information, clear the execution:
-     make DEBUG=-DDEBUG
-  4, run the demo with: 
+    # If you need to see the debug information, clear the execution:
+        make DEBUG=-DDEBUG    
+    
+    5, run the demo with: 
        sudo ./epd
   */