B&R X20 System Anwenderhandbuch Seite 253

Allgemeines Ablaufdiagramm
Yes
► DataSize = InputMTU_Size – MTU_Offset
► copy segment data e.g. memcpy(xxx, ADR(MTU_Data[MTU_Offset]), DataSize)
► MTU_Offset = MTU_Offset + DataSize
► RemainingSegmentSize = RemainingSegmentSize - DataSize
X20 System Anwenderhandbuch 4.30
Start
InputSyncBit = 1 ?
Yes
InputSyncAck = 1 ?
Yes
MTU_Offset = 0
(InputSequenceCounter –
InputSequenceAck)
AND 0x07 = 1 ?
Yes
RemainingSegmentSize = 0 ?
No
RemainingSegmentSize >
(InputMTU_Size – MTU_Offset) ?
► DataSize = RemainingSegmentSize
RemainingSegmentSize = 0 AND
(SegmentFlags AND 0x80) = 0 ?
No
RemainingSegmentSize = 0 AND
(SegmentFlags AND 0x40) = 0 ?
No
InputMTU_Size = MTU_Offset ?
No
Abbildung 47: Ablaufdiagramm für Input-Richtung
► InputSequenceAck = InputSequenceCounter
No
► RemainingSegmentSize = 0
► SegmentFlags = 0
No
InputSequenceAck > 0 ?
InputSyncAck = 1
No
► RemainingSegmentSize =
MTU_Data[MTU_Offset] AND 0b0011 1111
Yes
► SegmentFlags =
MTU_Data[MTU_Offset] AND 0b1100 0000
► MTU_Offset = MTU_Offset + 1
No
Yes
► Mark Frame as complete
Yes
Yes
► InputSequenceAck =
InputSequenceCounter
Zusätzliche Informationen
No
Yes
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