HDSPM_SyncRef3
case HDSPM_SyncRef3: return 8; /* AES 8 */
case HDSPM_SyncRef3+HDSPM_SyncRef0: return 9; /* TCO */
hdspm->control_register |= HDSPM_SyncRef3;
HDSPM_SyncRef3+HDSPM_SyncRef0;
HDSPM_SyncRef2|HDSPM_SyncRef3)