diff --git a/uc8151.py b/uc8151.py
index 1914892..feba60d 100644
--- a/uc8151.py
+++ b/uc8151.py
@@ -147,6 +147,7 @@ class UC8151:
     UPDATE_SPEED_MEDIUM=const(1)
     UPDATE_SPEED_FAST=const(2)
     UPDATE_SPEED_TURBO=const(3)
+    UPDATE_SPEED_ULTRA=const(4)
 
     def __init__(self,spi,*,cs,dc,rst,busy,speed=UPDATE_SPEED_DEFAULT,mirror_x=False,mirror_y=False,inverted=False):
         self.spi = spi
@@ -397,6 +398,35 @@ class UC8151:
       0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
       0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
       0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+      0x00, 0x00, 0x00, 0x00, 0x00, 0x00
+            ])
+        elif self.speed == UPDATE_SPEED_ULTRA:
+            VCOM = bytes([
+      0x00, 0x01, 0x01, 0x02, 0x00, 0x01,
+      0x00, 0x02, 0x02, 0x03, 0x00, 0x02,
+      0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+      0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+      0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+      0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+      0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+      0x00, 0x00
+            ])
+            WHITE = bytes([
+      0x54, 0x01, 0x01, 0x02, 0x00, 0x01,
+      0xa8, 0x02, 0x02, 0x03, 0x00, 0x02,
+      0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+      0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+      0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+      0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+      0x00, 0x00, 0x00, 0x00, 0x00, 0x00
+            ])
+            BLACK = bytes([
+      0xa8, 0x01, 0x01, 0x02, 0x00, 0x01,
+      0x54, 0x02, 0x02, 0x03, 0x00, 0x02,
+      0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+      0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+      0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+      0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
       0x00, 0x00, 0x00, 0x00, 0x00, 0x00
             ])
 
@@ -437,13 +467,15 @@ if  __name__ == "__main__":
     import random
 
     spi = SPI(0, baudrate=12000000, phase=0, polarity=0, sck=Pin(18), mosi=Pin(19), miso=Pin(16))
-    eink = UC8151(spi,cs=17,dc=20,rst=21,busy=26,speed=UPDATE_SPEED_TURBO)
+    eink = UC8151(spi,cs=17,dc=20,rst=21,busy=26,speed=UPDATE_SPEED_ULTRA)
     eink.fb.ellipse(10,10,10,10,1)
     eink.fb.ellipse(50,50,10,10,1)
 
-    x = random.randrange(100)
-    y = random.randrange(100)
-    eink.fb.text("TEST",x,y,1)
-    start = time.ticks_ms()
-    eink.update(blocking=True)
-    print("Update time:",time.ticks_ms() - start)
+    for _ in range(10):
+        x = random.randrange(100)
+        y = random.randrange(100)
+        eink.fb.text("TEST",x,y,1)
+        start = time.ticks_ms()
+        eink.update(blocking=True)
+        eink.fb.fill(0)
+        print("Update time:",time.ticks_ms() - start)