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FlexRay Communication Controller (FlexRAY)
PXN20 Microcontroller Reference Manual, Rev. 1
26-106
Freescale Semiconductor
Figure 26-124. Null Frame Transmission from HLck state
If a transmit message buffer is in the CCSa or HLckCCSa state at the start of the transmission slot, a null
frame is transmitted in any case, even if the message buffer is unlocked or committed before the
transmission slot starts. A transmit message buffer timing and state change diagram for null frame
transmission for this case is given in
Figure 26-125. Null Frame Transmission from HLck state with unlock
Since the null frame transmission will not use the message buffer data, the application can lock/unlock the
message buffer during null frame transmission. A transmit message buffer timing and state change
diagram for null frame transmission for this case is given in
Figure 26-126. Null Frame Transmission from Idle state with locking
26.6.6.2.7
Message Buffer Status Update
After the end of each slot, the PE generates the slot status vector. Depending on the this status, the
transmitted frame type, and the amount of transmitted data, the message buffer status is updated.
Message Buffer Status Update after Complete Message Transmission
The term complete message transmission refers to the fact that all payload data stored in the message
buffer were send to FlexRay bus. In this case, the controller updates the slot status field of the message
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Summary of Contents for PXN2020
Page 1: ...PXN20 Microcontroller Reference Manual Devices Supported PXN2020 PXN2120 PXN20RM Rev 1 06 2011...
Page 42: ...PXN20 Microcontroller Reference Manual Rev 1 lxiv Freescale Semiconductor...
Page 64: ...Introduction PXN20 Microcontroller Reference Manual Rev 1 1 22 Freescale Semiconductor...
Page 112: ...Signal Description PXN20 Microcontroller Reference Manual Rev 1 3 44 Freescale Semiconductor...
Page 118: ...Resets PXN20 Microcontroller Reference Manual Rev 1 4 6 Freescale Semiconductor...
Page 372: ...e200z6 Core Z6 PXN20 Microcontroller Reference Manual Rev 1 13 8 Freescale Semiconductor...
Page 412: ...e200z0 Core Z0 PXN20 Microcontroller Reference Manual Rev 1 14 14 Freescale Semiconductor...
Page 821: ...Media Local Bus MLB PXN20 Microcontroller Reference Manual Rev 1 Freescale Semiconductor 27 49...
Page 822: ...Media Local Bus MLB PXN20 Microcontroller Reference Manual Rev 1 27 50 Freescale Semiconductor...
Page 1376: ...Memory Map PXN20 Microcontroller Reference Manual Rev 1 A 118 Freescale Semiconductor...