auxg_bits
unsigned short auxg_bits; // bits written to auxiliary register G
tnt_priv->auxg_bits |= RPP2_BIT;
write_byte(&tnt_priv->nec7210_priv, tnt_priv->auxg_bits, AUXMR);
tnt_priv->auxg_bits &= ~RPP2_BIT;
write_byte(&tnt_priv->nec7210_priv, tnt_priv->auxg_bits, AUXMR);
tnt_priv->auxg_bits = AUXRG | NTNL_BIT;
write_byte(&tnt_priv->nec7210_priv, tnt_priv->auxg_bits, AUXMR);