diff --git a/src/test/kc/examples/mega65/linedrawing.c b/src/test/kc/examples/mega65/linedrawing.c
index 134699985..0cc982978 100644
--- a/src/test/kc/examples/mega65/linedrawing.c
+++ b/src/test/kc/examples/mega65/linedrawing.c
@@ -40,8 +40,8 @@ void lpoke(__zp unsigned long addr, char val) {
 // Graphics mode is 1 byte per pixel. Addressing is based on columns of 8px * 200px arranged to have linear addressing.
 // addr = (x/8) * 64 * 25 + (y*8) + (x&7)
 char line_dma_command[] = {
-  DMA_OPTION_LINE_XSTEP_LO, LOBYTE(25*64 - 8),  // Line X step bytes 64x25 
-  DMA_OPTION_LINE_XSTEP_HI, HIBYTE(25*64 - 8),  // Line X step bytes 64x25 
+  DMA_OPTION_LINE_XSTEP_LO, (25*64 - 8) & 0xff, // Line X step bytes 64x25
+  DMA_OPTION_LINE_XSTEP_HI, (25*64 - 8) >> 8,   // Line X step bytes 64x25
   DMA_OPTION_LINE_SLOPE_LO, 0,                  // Line Slope
   DMA_OPTION_LINE_SLOPE_HI, 0,                  // Line Slope
   DMA_OPTION_LINE_SLOPE_INIT_LO, LOBYTE(32768), // Line slope init
@@ -91,8 +91,8 @@ void line_dma_execute(unsigned long addr, unsigned int slope, unsigned int count
     // Count is number of pixels, i.e., dy.
     line_dma_command[LINE_DMA_COMMAND_COUNT_OFFSET] = LOBYTE(count);
     line_dma_command[LINE_DMA_COMMAND_COUNT_OFFSET + 1] = HIBYTE(count);
-    // Line mode active, major axis is Y
-    line_dma_command[LINE_DMA_COMMAND_MODE_OFFSET] = DMA_OPTION_LINE_MODE_ENABLE + (is_direction_y ? DMA_OPTION_LINE_MODE_DIRECTION_Y : 0x00) + (is_slope_negative ? DMA_OPTION_LINE_MODE_SLOPE_NEGATIVE : 0x00);
+    // Line mode
+    line_dma_command[LINE_DMA_COMMAND_MODE_OFFSET] = DMA_OPTION_LINE_MODE_ENABLE + (is_direction_y?DMA_OPTION_LINE_MODE_DIRECTION_Y:0) + (is_slope_negative?DMA_OPTION_LINE_MODE_SLOPE_NEGATIVE:0);
     // Set address of DMA list
     DMA->ADDRMB = 0;
     DMA->ADDRBANK = 0;
@@ -131,12 +131,12 @@ void main() {
   draw_line(160, 100, 319, 0, 4);  
   */
 
-  for(int x1=0;x1<320;x1+=10) {
+  for(int x1=0;x1<320;x1+=11) {
       draw_line(x1, 0, 160, 199, 5);      
       draw_line(160, 0, x1, 199, 5);      
   }
 
-  for(int y1=0;y1<200;y1+=10) {
+  for(int y1=0;y1<200;y1+=11) {
       draw_line(0, y1, 319, 100, 6);
       draw_line(0, 100, 319, y1, 6);
   }
@@ -219,9 +219,9 @@ void draw_line(int x1, int y1, int x2, int y2, unsigned char colour) {
       y2 = temp;
     }
 
-    // Use hardware divider to get the slope 
-    *MATH_MULTINA_INT0 = dx;
-    *MATH_MULTINB_INT0 = dy;
+    // Use hardware divider to get the slope
+    *MATH_MULTINA_INT0 = dx*2+1;
+    *MATH_MULTINB_INT0 = dy*2;
     *MATH_MULTINA_INT1 = 0;
     *MATH_MULTINB_INT1 = 0;
     
@@ -233,13 +233,12 @@ void draw_line(int x1, int y1, int x2, int y2, unsigned char colour) {
       lda MATH_DIVOUT_FRAC_INT1 @nooptimize
     }
     // Slope is the most significant bytes of the fractional part of the division result
-    // Perform rounding by examining the next bit also
-    unsigned int slope = (unsigned int)*MATH_DIVOUT_FRAC_INT1 + (((char)*MATH_DIVOUT_FRAC_CHAR1&0x80)?1:0);
-    unsigned int slope_init = 32768;
+    unsigned int slope = (unsigned int)*MATH_DIVOUT_FRAC_INT1;
     unsigned long addr = GRAPHICS + (unsigned int)(x1/8) * 64 * 25 + (unsigned int)(y1*8) + (unsigned char)(x1&7);
     unsigned int count = (unsigned int)dy;
-    char is_slope_negative = ((x2 - x1) < 0)?1:0;
-    line_dma_execute(addr, slope, count, colour, 1, is_slope_negative);
+    char is_slope_negative = ((x2 - x1) < 0) ? 1 : 0;
+    char is_direction_y = 1;
+    line_dma_execute(addr, slope, count, colour, is_slope_negative, is_direction_y);
   } else {
     // X is major axis
 
@@ -252,9 +251,9 @@ void draw_line(int x1, int y1, int x2, int y2, unsigned char colour) {
       y2 = temp;
     }
 
-    // Use hardware divider to get the slope 
-    *MATH_MULTINA_INT0 = dy;
-    *MATH_MULTINB_INT0 = dx;
+    // Use hardware divider to get the slope
+    *MATH_MULTINA_INT0 = dy*2+1;
+    *MATH_MULTINB_INT0 = dx*2;
     *MATH_MULTINA_INT1 = 0;
     *MATH_MULTINB_INT1 = 0;
 
@@ -265,14 +264,12 @@ void draw_line(int x1, int y1, int x2, int y2, unsigned char colour) {
       lda MATH_DIVOUT_FRAC_INT1 @nooptimize
       lda MATH_DIVOUT_FRAC_INT1 @nooptimize
     }
-
     // Slope is the most significant bytes of the fractional part of the division result
-    // Perform rounding by examining the next bit also
-    unsigned int slope = (unsigned int)*MATH_DIVOUT_FRAC_INT1 + (((char)*MATH_DIVOUT_FRAC_CHAR1&0x80)?1:0);
+    unsigned int slope = (unsigned int)*MATH_DIVOUT_FRAC_INT1;
     unsigned long addr = GRAPHICS + (unsigned int)(x1/8) * 64 * 25 + (unsigned int)(y1*8) + (unsigned char)(x1&7);
     unsigned int count = (unsigned int)dx;
     char is_slope_negative = ((y2 - y1) < 0) ? 1 : 0;
-    line_dma_execute(addr, slope, count, colour, 0, is_slope_negative);    
-
+    char is_direction_y = 0;
+    line_dma_execute(addr, slope, count, colour, is_slope_negative, is_direction_y);
   }
 }
\ No newline at end of file