 
   if(refresh) untztrument.writeDisplay();
 
-  while(usbMIDI.read()); // Discard incoming MIDI messages
 }

  e.setValue(bpm * 4);              // *4's for encoder detents
}

// Turn on (or off) one column of the display
void line(uint8_t x, boolean set) {
  for(uint8_t mask=1, y=0; y<8; y++, mask <<= 1) {

    line(col, true);
    for(uint8_t row=0, mask=1; row<8; row++, mask <<= 1) {
      if(grid[col] & mask) {
          noteOn(pgm_read_byte(&channel[row]), pgm_read_byte(&note[row]), 127);
      }
    }
    prevBeatTime = t;
