FlexRay Communication Controller (FLEXRAY)
MPC5510 Microcontroller Family Reference Manual, Rev. 1
Freescale Semiconductor
30-109
Preliminary
With the start of the next static or dynamic slot the module trigger the slot start transition SLS. This
changes the state of the subscribed receive message buffers from either CCBs to CCRx or from
HLckCCBs to HLckCCRx, respectively.
During the reception slot, the received frame data are written into the shadow buffers. For details on
receive shadow buffers, see
Section 30.6.6.3.5, “Receive Shadow Buffers Concept
”. The data and status
of the receive message buffers that are the CCRx or HLckCCRx are not modified in the reception slot.
30.6.6.3.3
Message Buffer Status Update
With the start of the next static or dynamic slot or with the start of the symbol window or NIT, the module
trigger the slot or segment start transition SSS. This transition changes the state of the receiving receive
message buffers from either CCRx to CCSu or from HLckCCRx to HLck, respectively.
If a message buffer was in the locked state HLckCCRx, no update will be performed. The received data
are lost. This is indicated by setting the Frame Lost Channel A/B Error Flag FRLA_EF/FRLB_EF in the
CHI Error Flag Register (CHIERFR)
If a message buffer was in the CCRx state it is now in the CCSu state. After the evaluation of the slot status
provided by the PE the message buffer is updated. The message buffer update depends on the slot status
bits and the segment the message buffer is assigned to. This is described in
.
Table 30-102. 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.