CURS_ENB
if (dga->csr & CURS_ENB) { /* if the cursor is enabled.. */
dga->csr &= ~CURS_ENB; /* ..and shut it off */
dga->csr &= ~CURS_ENB; /* shut off the cursor */
dga->csr |= CURS_ENB; /* ..turn it back on */
dga->csr |= CURS_ENB;