"LAT Unit and Transaction ID Bitfield" (SVC/MEM)

View Options: (help)

Focus:	Maintenance / Operation
Structures:	Abstract / Concrete

Ancestry:

0x000	pkt	LMEMEPU2DATA
0x00E	bf	TIDBF idents

Definition:

Alignment:	2-byte boundary
APID:	791/0x317
Attribute(s):
C type:	unsigned short
Length:	16 bits (2 bytes)
Offset:	0x00E

Description:

Bitfield containing the ID of the LAT unit that sent the telemetry and the transaction identifier of the telecommand that requested the telemetry.

Layout: (hide detail; help)

Start	Stop	Size		Item Type and Name
0	3	4		TLATUNIT latUnit
4	15	12		TTRANID tranID

TIDBF (bf)
|  TLATUNIT latUnit (0-3)
|  TTRANID tranID (4-15)

typedef struct _MEM_TIDBF_Bfl {

    #if ENDIANNESS_IS_BIG

    /* Source LAT Unit */
    unsigned short       latUnit:4;

    /* Transaction ID */
    unsigned short       tranID:12;

    #elif ENDIANNESS_IS_LITTLE

    /* Transaction ID */
    unsigned short       tranID:12;

    /* Source LAT Unit */
    unsigned short       latUnit:4;

    #else

    #error _FILE_ ENDIANNESS NOT DEFINED

    #endif

} __attribute__((packed)) MEM_TIDBF_Bfl;

typedef union _MEM_TIDBF {

    /* underlying unsigned short */
    unsigned short                  us;

    /* struct mapped bitfield */
    struct _MEM_TIDBF_Bfl           bf;

} MEM_TIDBF;

Fields:

TLATUNIT (index)

Attribute(s):  

Brief:  "Source LAT Unit"

Instance(s):  latUnit

LAT unit that sent the telemetry.

TTRANID (index)

Attribute(s):  

Brief:  "Transaction ID"

Instance(s):  tranID

Transaction identifier from the telecommand that requested the telemetry.