mfr4300 Freescale Semiconductor, Inc, mfr4300 Datasheet - Page 166

• Manufacturer Part Number: mfr4300
• Description: Flexray Communication Controllers
• Manufacturer: Freescale Semiconductor, Inc

FlexRay Module (FLEXRAYV2)
When the receive message buffer update has finished the status updated transition SU is triggered, which
changes the buffer state from CCSu to Idle. An example receive message buffer timing and state change
diagram for a normal frame reception is given in
The amount of message data written into the message buffer data field of the receive shadow buffer is
determined by the following two items:
If the message buffer is assigned to the message buffer segment 1, and the number of received bytes is
greater than 2*MBDSR.MBSEG1DS, the FlexRay module writes only 2*MBDSR.MBSEG1DS bytes
into the message buffer data field of the receive shadow buffer. If the number of received bytes is less than
2*MBDSR.MBSEG1DS, the FlexRay module writes only the received number of bytes and will not
change the trailing bytes in the message buffer data field of the receive shadow buffer. The same holds for
the message buffer segment 2 with MBDSR.MBSEG2DS.
166
1. the message buffer segment that the message buffer is assigned to, as defined by the
2. the message buffer data field size, as defined by the related field of the
3. the number of bytes received over the FlexRay bus
vSS!ValidFrame
Idle
Buffer Segment Size and Utilization Register
Register (MBDSR)
0
If the number of the last slot in the current communication cycle on a given
channel is n, then all receive message buffers assigned to this channel with
MBFIDRn.FID > n will not be updated at all.
BS
search[s+1]
vRF!Header!NFIndicator
Table 3-100. Receive Message Buffer Update (Continued)
slot s
CCBs
Figure 3-120. Message Reception Timing
x
MFR4300 Data Sheet, Rev. 3
No valid frame received.
- Message Buffer Data Field not updated.
- Frame Header Field not updated.
- Slot Status Field updated.
- DUP:= 0
- DVAL not changed.
- MBIF:= 1, if the slot was not an empty dynamic slot.
Note: An empty dynamic slot is indicated by the following frame and slot
SLS
NOTE
Figure
status bit values:
vSS!ValidFrame
vSS!ContentError
(MBSSUTR).
3-120.
message receive to receive shadow buffer
CCRx
= 0 and
slot s+1
= 0 and
Update description
vSS!SyntaxError
vSS!BViolation
Message Buffer Data Size
SSS
Freescale Semiconductor
= 0.
= 0 and
CCSu
SU
Message
slot s+2
Idle