~~ODT~~
===== ARINC 429 DATA =====
==== Type 0x38, ARINC 429 Data, Format 0 (ARINC 429 Data) ====
The ARINC 429 Data,
Format 0 packets are used to record data messages from an ARINC 429 data bus. ARINC 429 is
a unidirectional data bus that is commonly found on commercial and transport aircraft. Words
are 32 bits in length and most messages consist of a single data word. Messages are transmitted
at either 12.5 or 100 kbit/s from a transmitting system to one or more receiving systems. The
transmitter is always transmitting either 32-bit data words or the NULL state. An ARINC data
packet can contain multiple messages.
The layout of the CSDW is shown in Figure 6-36. The uMsgCount field indicates the
number of recorded ARINC 429 messages.
struct SuArinc429F0_ChanSpec
{
uint32_t uMsgCount : 16; // Message count
uint32_t Reserved : 16; //
}
Type 0x60 ARINC 429 Data Format 0 CSDW
Individual ARINC 429 data messages follow the CSDW. Each message is preceded with
an intra-packet data header followed by the ARINC 429 data word.
The layout of the ARINC 429 data message intra-packet data header is shown in
Figure 6-37. The uGapTime field is the time between the beginning of the preceding bus word
and the beginning of the current bus word in 0.1 microsecond increments. The uBusSpeed
field indicates the bit rate of the recorded bus message. The bParityError flag indicates the
presence of a parity data error. The bFormatError flag indicates the presence of one of
several types of data format errors. The uBusNum field identifies the specific ARINC 429 bus
associates with the recorded data message.
struct SuArinc429F0_Header
{
uint32_t uGapTime : 20; // Gap Time
uint32_t Reserved : 1; //
uint32_t uBusSpeed : 1; // Bus Speed
uint32_t bParityError : 1; // Parity Error
uint32_t bFormatError : 1; // Data type
uint32_t uBusNum : 8; // Bus number
}
Type 0x38 ARINC 429 Data Format 0 intra-packet data header.
The layout of the individual ARINC 429 data work is shown in Figure 6-38. Refer to the
ARINC 429 standard for the interpretation of the specific data fields.
struct SuArinc429F0_Data
{
uint32_t uLabel : 8; // Label
uint32_t uSDI : 2; // Source/Destination ID
uint32_t uData : 19; // Data
uint32_t uSSM : 2; // Sign/Status Matrix
uint32_t uParity : 1; // Parity
}
Type 0x38 ARINC 429 data format.
----
==== Type 0x39 - 0x3F, ARINC 429 Data, Format 1 - Format 7 ====
Reserved for future use.