diff --git a/RaspberryPi&JetsonNano/python/lib/waveshare_epd/epd2in7.py b/RaspberryPi&JetsonNano/python/lib/waveshare_epd/epd2in7.py
index 5ca0739..6482fb1 100644
--- a/RaspberryPi&JetsonNano/python/lib/waveshare_epd/epd2in7.py
+++ b/RaspberryPi&JetsonNano/python/lib/waveshare_epd/epd2in7.py
@@ -272,7 +272,8 @@ class EPD:
         epdconfig.spi_writebyte([command])
         if data:
             epdconfig.digital_write(self.dc_pin, epdconfig.GPIO.HIGH)  # HIGH: write data
-            [epdconfig.spi_writebyte([byte]) for byte in data]
+            # [epdconfig.spi_writebyte([byte]) for byte in data]
+            epdconfig.spi_writebytes2(data)
 
     def set_lut(self):
         look_up_tables = {
diff --git a/RaspberryPi&JetsonNano/python/lib/waveshare_epd/epdconfig.py b/RaspberryPi&JetsonNano/python/lib/waveshare_epd/epdconfig.py
index 3dc4f62..9d3be62 100644
--- a/RaspberryPi&JetsonNano/python/lib/waveshare_epd/epdconfig.py
+++ b/RaspberryPi&JetsonNano/python/lib/waveshare_epd/epdconfig.py
@@ -37,6 +37,12 @@ def spi_writebyte(data):
 	SPI.writebytes(data)
 	GPIO.output(CS_PIN, GPIO.HIGH)
 
+def spi_writebytes2(data):
+	# manual CS on ROCK64
+	GPIO.output(CS_PIN, GPIO.LOW)
+	SPI.writebytes2(data)
+	GPIO.output(CS_PIN, GPIO.HIGH)
+
 def module_init():
 	GPIO.setmode(GPIO.BOARD)
 	GPIO.setwarnings(False)