Freescale Semiconductor PXR4030, Reference Manual

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FlexRay Communication Controller (FLEXRAY)
22-90 Freescale Semiconductor
PXR40 Microcontroller Reference Manual, Rev. 1
22.6.5.2.2 Data Field Offset Description
Data Field Offset Content
For a detailed description of the Data Field Offset, see Section 22.6.2.1.2, Data Field Offset .
Data Field Offset Access
The application shall program the Data Field Offset when configuring the message buffers either in the
POC:config state or when the message buffer is disabled.
22.6.5.2.3 Slot Status Description
The slot status is a read-only structure for the application and a write-only structure for the controller. The
meaning and content of the slot status in the message buffer header field depends on the message buffer
type.
Receive Message Buffer and Receive FIFO Slot Status Description
This section describes the slot status structure for the individual receive message buffers and receive
FIFOs. The content of the slot status structure for receive message buffers depends on the message buffer
type and on the channel assignment for individual receive message buffers as given by
Table 22-87 .
The meaning of the bits in the slot status structure is explained in Table 22-88 .
PLDLEN Payload Length — This field is checked and used as described in Frame Header Checks .
HDCRC Header CRC — This field provides the value of the Header CRC field for the frame transmitted from the message
buffer.
Table 22-87. Receive Message Buffer Slot Status Content
Receive Message Buffer Type Slot Status Content
Individual Receive Message Buffer assigned to both channels
MBCCSRn[CHA]=1 and MBCCSRn[CHB]=1
see Figure 22-112
Individual Receive Message Buffer assigned to channel A
MBCCSRn[CHA]=1 and MBCCSRn[CHB[=0
see Figure 22-113
Individual Receive Message Buffer assigned to channel B
MBCCSRn[CHA]=0 and MBCCSRn[CHB]=1
see Figure 22-114
Receive FIFO Channel A Message Buffer see Figure 22-113
Receive FIFO Channel B Message Buffer see Figure 22-114
Table 22-86. Frame Header Field Descriptions (Transmit Message Buffer) (continued)
Field Description