This structure indicates valid and invalid PNTM elements.
typedef struct tagPNAVTM
{ 
DWORD dwStructureSize;
DWORD dwAv1;
DWORD dwPNReserved;
} PNAVTM;
| Flag | Bit | Description | 
| PN_ATM_MILLISEC | 0 | Millisecond is valid or invalid. | 
| PN_ATM_DAY | 1 | Day is valid or invalid. | 
| Reserved for future use | 2-31 |