function clearScreenDithered() {
    //
    // set all the attribute values
    const attr = makeAttribute(my.ink, my.paper, false)
    displayColours.fill(attr)
    //
    // fill the display with an odd pixel pattern
    displayPixels.fill(0b01010101)
    //
    // fill every other line with an even pixel pattern;
    // it is necessary to do this even/odd alternation otherwise
    // the pixels will align into lines instead of a checkerboard
    for (let i = 0; i < (XMAX * YMAX); i += COLUMNS * 2)
       displayPixels.fill(0b10101010, i, i + COLUMNS)
} //                                                         clearScreenDithered

/** clearScreenDithered():
 *  Clears the screen using a mix of two colours.
 */
Clears the screen using a mix of two colours.
Clears the screen using a mix of two colours .
function clearScreenDithered() {
    const attr = makeAttribute(my.ink, my.paper, false)
    displayColours.fill(attr)
    displayPixels.fill(0b01010101)
    for (let i = 0; i < (XMAX * YMAX); i += COLUMNS * 2)
       displayPixels.fill(0b10101010, i, i + COLUMNS)
} 
function clearScreenDithered ( ) { const attr = makeAttribute ( my . ink , my . paper , false ) displayColours . fill ( attr ) displayPixels . fill ( 0b01010101 ) for ( let i = 0 ; i < ( XMAX * YMAX ) ; i += COLUMNS * 2 ) displayPixels . fill ( 0b10101010 , i , i + COLUMNS ) }
clearScreenDithered():
  Clears the screen using a mix of two colours.
clearScreenDithered () : Clears the screen using a mix of two colours .
//
 // set all the attribute values
 //
 // fill the display with an odd pixel pattern
 //
 // fill every other line with an even pixel pattern;
 // it is necessary to do this even/odd alternation otherwise
 // the pixels will align into lines instead of a checkerboard
 //                                                         clearScreenDithered
