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Reference Manual AFDX / ARINC 664 Application Interface Library
Section 4 – Function Reference: Transmitter Functions
For Header Type
FDX_TX_FRAME_HEADER_GENERIC
see following description.
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typedef struct {
AiUInt8
uc_FrameType;
TY_FDX_TX_FRAME_ATTRIB
x_FrameAttrib;
TY_FDX_TX_INSTR_ATTRIB
x_InstrAttrib;
} TY_FDX_TX_FRAME_HEADER;
Note:
The FdxInitTxFrameHeader function supports a default initialization of this
structure (see this function in the chapter ‘Target Independent
Administration Functions’
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The Type of the frame:
Value:
Description:
FDX_TX_FRAME_STD
Standard Generic Tx Frame
FDX_TX_FRAME_INSTR Instruction
Type
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This structure describes the Frame Attributes in case of
FDX_TX_FRAME_STD
uc_FrameType.
typedef struct {
AiUInt16
uw_FrameSize;
AiUInt32
ul_InterFrameGap;
AiUInt32
ul_PacketGroupWaitTime;
AiUInt8 uc_PayloadBufferMode;
AiUInt8 uc_PayloadGenerationMode;
AiUInt32
ul_BufferQueueHandle;
AiUInt8 uc_ExternalStrobe;
AiUInt8 uc_PreambleCount;
AiUInt32
ul_Skew;
AiUInt8 uc_NetSelect;
AiUInt8 uc_FrameStartMode;
AiUInt32
ul_PhysErrorInjection;
AiUInt16
uw_SequenceNumberInit;
AiUInt16
uw_SequenceNumberOffset;
AiUInt8 uc_TxIntEnable
AiUInt32
ul_IntIdent
}
TY_FDX_TX_FRAME_ATTRIB;
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;
;
Total size of the associated frame in Bytes (incl. CRC). Short and Long Frame Error
Conditions are possible by setting the corresponding values. AFDX compliant values are
64…1518. For Frame length less than 60 no proper frame transmission is guaranteed.
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This value defines the interframe gap between the preceding frame and the current
frame with a resolution of 40ns, measured from the end of the last bit fo the preceding
frame to the first preamble bit of the actual frame.
To implement a physical gap between the frames, a minimum interframe gap of 120 ns (
value = 3 ) shall be initialized. The maximum provided interframe gap will be up to
approx. 655us (14 Bits are used for encoding). If the Packet group Wait Time is used,
this field shall be initialized with zero. This Gap is only used if
uc_FrameStartMode
is
set to FDX_TX_START_FRAME_IFG.
