/* Scroll one line of characters up on the screen.  */
static void tftTextScrollUp(void)
/* Scroll one line of characters up on the screen.  */
static void tftTextScrollUp(void)
{
  int y;
  int x;
  for (y = 0; y < (LINES - 1); y++)
  {
    for (x = 0; x < CHARS; x++)
    {
      charBuffer[y][x] = charBuffer[y + 1][x];
    }
  }
  for (x = 0; x < CHARS; x++)
  {
    charBuffer[LINES - 1][x] = 0;
  }
  xpos       = 0;
  ypos       = LINES - 1;
  fullUpdate = true;
}