NXP Semiconductors PXN2020 - Page 730

FlexRay Communication Controller (FlexRAY)
PXN20 Microcontroller Reference Manual, Rev. 1
26-116 Freescale Semiconductor
double transmit message buffer are given in Figure 26-133. A description of the states is given in
Table 26-108. The description tables also provide the access scheme for the access regions.
The status bits MBCCSRn[EDS] and MBCCSRn[LCKS] provide the application with the required
message buffer status information. The internal status information is not visible to the application.
26.6.6.4.2 Message Buffer States
This section describes the transmit message buffer states and provides a state diagram.
Figure 26-132. Double Transmit Message Buffer State Diagram (Commit Side)
A description of the states of the commit side of a double transmit message buffer is given in Table 26-107.
Table 26-107. Double Transmit Message Buffer State Description (Commit Side)
State
MBCCSR(2n) Access Region
Description
EDS LCKS Appl. Module
common states
HDis 0 0 CFG – Dis
abled - Message Buffer under configuration.
Commit Side can not be used for internal message transfer.
CCITx 1 0 – ITX I
nternal Message Transfer - Message Buffer Data transferred from
commit side to transmit side.
commit side specific states
Idle 1 0 – ITX,
SS
Idle
- Message Buffer Commit Side is idle.
Commit Side can be used for internal message transfer.
HDisLck 0 1 CFG
SS
Disabled and Locked - Message Buffer under configuration.
Commit Side can not be used for internal message transfer.
HLck 1 1 MSG
SS
Locked - Applications access to data, control, and status.
Commit Side can not be used for internal message transfer.
HDis
RESET_STATE
HD
HE
Idle
IS
IE
CCITx
HLck
HE
HL
HU
HDisLck
HU
HD
HL