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FlexRay Communication Controller (FlexRay)
MPC5644A Microcontroller Reference Manual, Rev. 6
Freescale Semiconductor
1567
NOTE
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
FR_MBFIDRn[FID] >
n
will not be updated at all.
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
Figure 33-139. Message reception timing
The amount of message data written into the message buffer data field of the receive shadow buffer is
determined by the following two items:
1. the message buffer segment that the message buffer is assigned to, as defined by the
Buffer Segment Size and Utilization Register (FR_MBSSUTR)
.
Table 33-115. Receive message buffer update
vSS!ValidFrame
vRF!Header!NFIndicator
Update description
1
1
Valid non-null frame received
- Message Buffer Data Field updated
- Frame Header Field updated
- Slot Status Field updated
- DUP = 1
- DVAL = 1
- MBIF = 1
1
0
Valid null frame received
- Message Buffer Data Field
not
updated
- Frame Header Field
not
updated
- Slot Status Field updated
- DUP = 0
- DVAL
not
changed
- MBIF = 1
0
x
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 status bit values:
vSS!ValidFrame
= 0 and
vSS!SyntaxError
= 0 and
vSS!ContentError
= 0 and
vSS!BViolation
= 0.
search[s+1]
M
T st
ar
t
BS
slot s
SLS
SU
CCBs CCRx
slot s+1
Idle
M
T st
ar
t
Idle
slot s+2
slot
st
art
slot
st
art
M
T st
ar
t
message receive to receive shadow buffer
SSS
CCSu
slot st
art
Summary of Contents for MPC5644A
Page 2: ...MPC5644A Microcontroller Reference Manual Rev 6 2 Freescale Semiconductor...
Page 24: ...MPC5644A Microcontroller Reference Manual Rev 6 24 Freescale Semiconductor...
Page 26: ...MPC5644A Microcontroller Reference Manual Rev 6 26 Freescale Semiconductor...
Page 52: ...Introduction MPC5644A Microcontroller Reference Manual Rev 6 52 Freescale Semiconductor...
Page 56: ...Memory Map MPC5644A Microcontroller Reference Manual Rev 6 56 Freescale Semiconductor...
Page 1228: ...Decimation Filter MPC5644A Microcontroller Reference Manual Rev 6 1228 Freescale Semiconductor...
Page 1440: ...FlexCAN Module MPC5644A Microcontroller Reference Manual Rev 6 1440 Freescale Semiconductor...