diff --git a/README.md b/README.md
index b1d8ebd0..75bdcc7f 100644
--- a/README.md
+++ b/README.md
@@ -410,7 +410,8 @@ u8glib comes with a wide range of fonts for small displays. Since they need to b
 They'll be available as `u8g.<font_name>` in Lua.
 
 #####Bitmaps
-Bitmaps and XBMs are supplied as strings to `drawBitmap()` and `drawXBM()`. This off-loads all data handling from the u8g module to generic methods for binary files. See `lua_examples/u8glib/u8g_bitmaps.lua`. Binary files can be uploaded with [nodemcu-uploader.py](https://github.com/kmpm/nodemcu-uploader).
+Bitmaps and XBMs are supplied as strings to `drawBitmap()` and `drawXBM()`. This off-loads all data handling from the u8g module to generic methods for binary files. See `lua_examples/u8glib/u8g_bitmaps.lua`.
+In contrast to the source code based inclusion of XBMs into u8glib, it's required to provide precompiled binary files. This can be performed online with [Online-Utility's Image Converter](http://www.online-utility.org/image_converter.jsp): Convert from XBM to MONO format and upload the binary result with [nodemcu-uploader.py](https://github.com/kmpm/nodemcu-uploader).
 
 #####Unimplemented functions
 - [ ] Cursor handling
diff --git a/lua_examples/u8glib/u8g_bitmaps.lua b/lua_examples/u8glib/u8g_bitmaps.lua
index 1b388e41..4ac8a60f 100644
--- a/lua_examples/u8glib/u8g_bitmaps.lua
+++ b/lua_examples/u8glib/u8g_bitmaps.lua
@@ -2,9 +2,9 @@
 -- setup I2c and connect display
 function init_i2c_display()
      -- SDA and SCL can be assigned freely to available GPIOs
-     sda = 5 -- GPIO14
-     scl = 6 -- GPIO12
-     sla = 0x3c
+     local sda = 5 -- GPIO14
+     local scl = 6 -- GPIO12
+     local sla = 0x3c
      i2c.setup(0, sda, scl, i2c.SLOW)
      disp = u8g.ssd1306_128x64_i2c(sla)
 end
@@ -15,9 +15,9 @@ function init_spi_display()
      -- Hardware SPI MOSI = GPIO13
      -- Hardware SPI MISO = GPIO12 (not used)
      -- CS, D/C, and RES can be assigned freely to available GPIOs
-     cs  = 8 -- GPIO15, pull-down 10k to GND
-     dc  = 4 -- GPIO2
-     res = 0 -- GPIO16
+     local cs  = 8 -- GPIO15, pull-down 10k to GND
+     local dc  = 4 -- GPIO2
+     local res = 0 -- GPIO16
 
      spi.setup(1, spi.MASTER, spi.CPOL_LOW, spi.CPHA_LOW, spi.DATABITS_8, 0)
      disp = u8g.ssd1306_128x64_spi(cs, dc, res)
diff --git a/lua_examples/u8glib/u8g_graphics_test.lua b/lua_examples/u8glib/u8g_graphics_test.lua
index 27c7a346..1985b461 100644
--- a/lua_examples/u8glib/u8g_graphics_test.lua
+++ b/lua_examples/u8glib/u8g_graphics_test.lua
@@ -2,9 +2,9 @@
 -- setup I2c and connect display
 function init_i2c_display()
      -- SDA and SCL can be assigned freely to available GPIOs
-     sda = 5 -- GPIO14
-     scl = 6 -- GPIO12
-     sla = 0x3c
+     local sda = 5 -- GPIO14
+     local scl = 6 -- GPIO12
+     local sla = 0x3c
      i2c.setup(0, sda, scl, i2c.SLOW)
      disp = u8g.ssd1306_128x64_i2c(sla)
 end
@@ -15,9 +15,9 @@ function init_spi_display()
      -- Hardware SPI MOSI = GPIO13
      -- Hardware SPI MISO = GPIO12 (not used)
      -- CS, D/C, and RES can be assigned freely to available GPIOs
-     cs  = 8 -- GPIO15, pull-down 10k to GND
-     dc  = 4 -- GPIO2
-     res = 0 -- GPIO16
+     local cs  = 8 -- GPIO15, pull-down 10k to GND
+     local dc  = 4 -- GPIO2
+     local res = 0 -- GPIO16
 
      spi.setup(1, spi.MASTER, spi.CPOL_LOW, spi.CPHA_LOW, spi.DATABITS_8, 0)
      disp = u8g.ssd1306_128x64_spi(cs, dc, res)
@@ -91,17 +91,6 @@ function ascii_1()
      end
 end
 
-function ascii_2()
-     local x, y, s
-     disp:drawStr(0, 0, "ASCII page 2")
-     for y = 0, 5, 1 do
-          for x = 0, 15, 1 do
-               s = y*16 + x + 160
-               disp:drawStr(x*7, y*10+10, string.char(s))
-          end
-     end
-end
-
 function extra_page(a)
      disp:drawStr(0, 12, "setScale2x2")
      disp:setScale2x2()
@@ -131,8 +120,6 @@ function draw(draw_state)
      elseif (component == 6) then
           ascii_1()
      elseif (component == 7) then
-          ascii_2()
-     elseif (component == 8) then
           extra_page(bit.band(draw_state, 7))
      end
 end
diff --git a/lua_examples/u8glib/u8g_rotation.lua b/lua_examples/u8glib/u8g_rotation.lua
index 6d81c779..81d81e6f 100644
--- a/lua_examples/u8glib/u8g_rotation.lua
+++ b/lua_examples/u8glib/u8g_rotation.lua
@@ -2,9 +2,9 @@
 -- setup I2c and connect display
 function init_i2c_display()
      -- SDA and SCL can be assigned freely to available GPIOs
-     sda = 5 -- GPIO14
-     scl = 6 -- GPIO12
-     sla = 0x3c
+     local sda = 5 -- GPIO14
+     local scl = 6 -- GPIO12
+     local sla = 0x3c
      i2c.setup(0, sda, scl, i2c.SLOW)
      disp = u8g.ssd1306_128x64_i2c(sla)
 end
@@ -15,9 +15,9 @@ function init_spi_display()
      -- Hardware SPI MOSI = GPIO13
      -- Hardware SPI MISO = GPIO12 (not used)
      -- CS, D/C, and RES can be assigned freely to available GPIOs
-     cs  = 8 -- GPIO15, pull-down 10k to GND
-     dc  = 4 -- GPIO2
-     res = 0 -- GPIO16
+     local cs  = 8 -- GPIO15, pull-down 10k to GND
+     local dc  = 4 -- GPIO2
+     local res = 0 -- GPIO16
 
      spi.setup(1, spi.MASTER, spi.CPOL_LOW, spi.CPHA_LOW, spi.DATABITS_8, 0)
      disp = u8g.ssd1306_128x64_spi(cs, dc, res)