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Chapter 13 FlexRay Communication Controller (FLEXRAY)
MC9S12XF - Family Reference Manual, Rev.1.19
536
Freescale Semiconductor
10
EDT
Enable/Disable Trigger — This trigger bit is used to enable and disable a message buffer. The message buffer
enable is triggered when the application writes 1 to this bit and the message buffer is disabled, i.e. the EDS status
bit is 0. The message buffer disable is triggered when the application writes 1 to this bit and the message buffer
is enabled, i.e. the EDS status bit is 1.
0 No effect
1 message buffer enable/disable triggered
Note: If the application writes 1 to this bit, the write access to all other bits is ignored.
9
LCKT
Lock/Unlock Trigger — This trigger bit is used to lock and unlock a message buffer. The message buffer lock
is triggered when the application writes 1 to this bit and the message buffer is not locked, i.e. the LCKS status
bit is 0. The message buffer unlock is triggered when the application writes 1 to this bit and the message buffer
is locked, i.e. the LCKS status bit is 1.
0 No effect
1 Trigger message buffer lock/unlock
Note: If the application writes 1 to this bit and 0 to the EDT bit, the write access to all other bits is ignored.
8
MBIE
Message Buffer Interrupt Enable — This control bit denes whether the message buffer will generate an
interrupt request when its MBIF ag is set.
0 Interrupt request generation disabled
1 Interrupt request generation enabled
Message Buffer Status
4
DUP
Data Updated — This status bit applies only to receive message buffers. It is always 0 for transmit message
buffers. This bit provides information whether the frame header in the message buffer header eld and the
description of the update condtions.
0 Frame Header and Message buffer data eld not updated.
1 Frame Header and Message buffer data eld updated.
3
DVAL
Data Valid — The semantic of this status bit depends on the message buffer type and transfer direction.
Receive Message Buffer: Indicates whether the message buffer data eld contains valid frame data. See
0 message buffer data eld contains no valid frame data
1 message buffer data eld contains valid frame data
Single Transmit Message Buffer: Indicates whether the message is transferred again due to the state
transmission mode of the message buffer.
0 Message transferred for the rst time.
1 Message will be transferred again.
Double Transmit Message Buffer: For the commit side it is always 0. For the transmit side it indicates whether
the message is transferred again due to the state transmission mode of the message buffer.
0 Message transferred for the rst time.
1 Message will be transferred again.
2
EDS
Enable/Disable Status — This status bit indicates whether the message buffer is enabled or disabled.
0 Message buffer is disabled.
1 Message buffer is enabled.
Table 13-78. MBCCSRn Field Descriptions (Sheet 2 of 3)
Field
Description