diff --git a/csrc/u8g2_hvline.c b/csrc/u8g2_hvline.c
index 43e2cfe6..86815ba4 100644
--- a/csrc/u8g2_hvline.c
+++ b/csrc/u8g2_hvline.c
@@ -120,9 +120,11 @@ static void u8g2_draw_hv_line_2dir(u8g2_t *u8g2, u8g2_uint_t x, u8g2_uint_t y, u
 
   y -= u8g2->tile_curr_row*8;
   
-  h = u8g2->pixel_buf_height;
-  w = u8g2->pixel_buf_width;
   
+  h = u8g2->pixel_buf_height;		// this must be the real buffer height
+  w = u8g2->pixel_buf_width;		// this could be replaced by u8g2->u8x8.display_info->pixel_width
+
+
   if ( dir == 0 )
   {
     if ( y >= h )
diff --git a/csrc/u8g2_setup.c b/csrc/u8g2_setup.c
index 6ea23629..beb08d61 100644
--- a/csrc/u8g2_setup.c
+++ b/csrc/u8g2_setup.c
@@ -103,7 +103,7 @@ void u8g2_update_dimension_r0(u8g2_t *u8g2)
   u8g2_update_dimension_common(u8g2);
 
   u8g2->user_x0 = 0;
-  u8g2->user_x1 = u8g2->width;	/* pixel_buf_width replaced with width */
+  u8g2->user_x1 = u8g2->pixel_buf_width;	/* pixel_buf_width replaced with width */
   
   u8g2->user_y0 = u8g2->buf_y0;
   u8g2->user_y1 = u8g2->buf_y1;
@@ -123,7 +123,7 @@ void u8g2_update_dimension_r1(u8g2_t *u8g2)
   u8g2->user_x1 = u8g2->buf_y1;
   
   u8g2->user_y0 = 0;
-  u8g2->user_y1 = u8g2->width;	/* pixel_buf_width replaced with width */
+  u8g2->user_y1 = u8g2->height;	/* pixel_buf_width replaced with height (which is the real pixel width) */
   
   //printf("x0=%d x1=%d y0=%d y1=%d\n", 
    //   u8g2->user_x0, u8g2->user_x1, u8g2->user_y0, u8g2->user_y1);
@@ -154,7 +154,7 @@ void u8g2_update_dimension_r3(u8g2_t *u8g2)
   u8g2->user_x1 = u8g2->width - u8g2->buf_y0;
   
   u8g2->user_y0 = 0;
-  u8g2->user_y1 = u8g2->width;	/* pixel_buf_width replaced with width */
+  u8g2->user_y1 = u8g2->height;	/* pixel_buf_width replaced with height (pixel_width) */
 
 //  printf("x0=%d x1=%d y0=%d y1=%d\n", 
 //      u8g2->user_x0, u8g2->user_x1, u8g2->user_y0, u8g2->user_y1);
diff --git a/csrc/u8x8.h b/csrc/u8x8.h
index 52fdaec9..b76dabfe 100644
--- a/csrc/u8x8.h
+++ b/csrc/u8x8.h
@@ -228,7 +228,7 @@ struct u8x8_display_info_struct
   uint8_t default_x_offset;	/* default x offset for the display */
  
  /* pixel width is not used by the u8x8 procedures */
- /* instead it will be used by the u8g2 procedure, because the pixel dimension can */
+ /* instead it will be used by the u8g2 procedures, because the pixel dimension can */
  /* not always be calculated from the tile_width/_height */
  /* the following conditions must be true: */
  /* pixel_width <= tile_width*8 */
diff --git a/csrc/u8x8_d_uc1701_dogs102.c b/csrc/u8x8_d_uc1701_dogs102.c
index b9807141..10c32889 100644
--- a/csrc/u8x8_d_uc1701_dogs102.c
+++ b/csrc/u8x8_d_uc1701_dogs102.c
@@ -115,7 +115,7 @@ static const u8x8_display_info_t u8x8_uc1701_display_info =
   /* i2c_bus_clock_100kHz = */ 37,
   /* data_setup_time_ns = */ 30,
   /* write_pulse_width_ns = */ 40,
-  /* tile_width = */ 13,
+  /* tile_width = */ 13,		/* width of 13*8=104 pixel */
   /* tile_hight = */ 8,
   /* default_x_offset = */ U8X8_IF_DEFAULT_NORMAL_OR_FLIP(0, 30),
   /* pixel_width = */ 102,
diff --git a/sys/utf8/common/u8x8_d_utf8.c b/sys/utf8/common/u8x8_d_utf8.c
index 1903fe61..b6e3f847 100644
--- a/sys/utf8/common/u8x8_d_utf8.c
+++ b/sys/utf8/common/u8x8_d_utf8.c
@@ -4,15 +4,16 @@
 #include <stdlib.h>
 #include <string.h>
 
-#define CHGR_WIDTH 96
+//#define CHGR_WIDTH 96
+#define CHGR_WIDTH 102
 #define CHGR_HEIGHT 32
 unsigned char chgr_bitmap[CHGR_HEIGHT/2][CHGR_WIDTH/2];
 
 unsigned char *chgr_bitmap_pos(unsigned x, unsigned y)
 {
-  if ( x > CHGR_WIDTH )
+  if ( x >= CHGR_WIDTH )
     return NULL;
-  if ( y > CHGR_HEIGHT )
+  if ( y >= CHGR_HEIGHT )
     return NULL;
   return &(chgr_bitmap[y/2][x/2]);  
 }
@@ -146,8 +147,8 @@ static const u8x8_display_info_t u8x8_utf8_info =
   /* i2c_bus_clock_100kHz = */ 0,
   /* data_setup_time_ns = */ 0,
   /* write_pulse_width_ns = */ 0,
-  /* tile_width = */ (CHGR_WIDTH)/8,
-  /* tile_hight = */ (CHGR_HEIGHT)/8,
+  /* tile_width = */ (CHGR_WIDTH+7)/8,
+  /* tile_hight = */ (CHGR_HEIGHT+7)/8,
 #if U8X8_DEFAULT_FLIP_MODE == 0 
   /* default_x_offset = */ 0,
 #else
@@ -219,7 +220,7 @@ void u8x8_Setup_Utf8(u8x8_t *u8x8)
 
 void u8g2_SetupBuffer_Utf8(u8g2_t *u8g2, const u8g2_cb_t *u8g2_cb)
 {
-  static uint8_t buf[CHGR_WIDTH*8];
+  static uint8_t buf[CHGR_WIDTH*8];   // i guess this is to big. it should be (CHGR_WIDTH+7)/8
   
   u8x8_Setup_Utf8(u8g2_GetU8x8(u8g2));
 
diff --git a/sys/utf8/frame_rotate_picture_loop/Makefile b/sys/utf8/frame_rotate_picture_loop/Makefile
new file mode 100644
index 00000000..9479db8a
--- /dev/null
+++ b/sys/utf8/frame_rotate_picture_loop/Makefile
@@ -0,0 +1,14 @@
+CC = gcc
+
+CFLAGS = -g -W -Wall -Wextra -Wcast-qual -Wno-overlength-strings -Wno-unused-parameter -I../../../csrc/. 
+
+SRC = $(shell ls ../../../csrc/*.c) $(shell ls ../common/*.c ) main.c 
+
+OBJ = $(SRC:.c=.o)
+
+u8g2_utf8: $(OBJ) 
+	$(CC) $(CFLAGS) $(LDFLAGS) $(OBJ) -o u8g2_utf8
+
+clean:	
+	-rm $(OBJ) u8g2_utf8
+
diff --git a/sys/utf8/frame_rotate_picture_loop/main.c b/sys/utf8/frame_rotate_picture_loop/main.c
new file mode 100644
index 00000000..f1b98dbe
--- /dev/null
+++ b/sys/utf8/frame_rotate_picture_loop/main.c
@@ -0,0 +1,49 @@
+/*
+  this example was written to debug a problem with a display width, which
+  is not multiple of 8.
+  the display width is set to 102 for this purpose
+*/
+
+
+
+#include "u8g2.h"
+#include <stdio.h>
+
+
+  
+u8g2_t u8g2;
+
+int main(void)
+{
+
+  u8g2_SetupBuffer_Utf8(&u8g2, U8G2_R1);
+  
+  
+  u8g2_InitDisplay(&u8g2);
+  u8g2_SetPowerSave(&u8g2, 0);  
+  
+  u8g2_SetFont(&u8g2, u8g2_font_6x13_tf);
+  u8g2_SetFontDirection(&u8g2, 0);
+  
+  u8g2_FirstPage(&u8g2);
+  do
+  {      
+    
+    //u8g2_DrawFrame(&u8g2, 0, 0, 
+    //  u8g2_GetDisplayWidth(&u8g2), u8g2_GetDisplayHeight(&u8g2));
+    //u8g2_DrawHLine(&u8g2, 0, 0, u8g2_GetDisplayWidth(&u8g2));
+    u8g2_DrawHLine(&u8g2, 0, u8g2_GetDisplayHeight(&u8g2)-1, u8g2_GetDisplayWidth(&u8g2));
+    //u8g2_DrawHLine(&u8g2, 0, 32, 10);
+    // u8g2_DrawStr(&u8g2, 10, 20, "Frame");
+    //u8g2_DrawStr(&u8g2, u8g2_GetDisplayWidth(&u8g2)-9, 10, "Frame");
+    //u8g2_DrawStr(&u8g2, u8g2_GetDisplayWidth(&u8g2)-8, 20, "Frame");
+    //u8g2_DrawStr(&u8g2, u8g2_GetDisplayWidth(&u8g2)-7, 30, "Frame");
+  } while( u8g2_NextPage(&u8g2) );
+    
+  utf8_show();
+  
+  printf("DisplayWidth = %d\n", u8g2_GetDisplayWidth(&u8g2));
+  
+  return 0;
+}
+