mfr4200 Freescale Semiconductor, Inc, mfr4200 Datasheet - Page 157

• Manufacturer Part Number: mfr4200
• Description: Flexray Communication Controllers
• Manufacturer: Freescale Semiconductor, Inc

1 – Double transmit message buffer.
3.4.1.10 TT — Type of Transmission
The host can configure the type of transmission used for a buffer. Therefore, the CC can combine two types
of systems — event and state driven systems.
0 – Event type of transmission
1 – State type of transmission
3.4.1.11 VALID — Message Buffer Valid Flag
The semantic of this status bit depends on the configuration of the message buffer.
Transmit message buffer:
The valid bit indicates whether a transmit buffer holds valid for transmission data or not.
The CC clears the VALID bit of a transmit message buffer when the host locks it.
When the host has committed the buffer for transmission (see the BUFCMT bit description in
Section 3.4.1, “Message Buffer Control, Configuration and Status
controller performs the following operations:
1 – The corresponding buffer contains a semantically valid frame to be transmitted.
0 – The corresponding buffer does not contain a semantically valid frame to be transmitted.
Receive message buffer
The VALID bit indicates whether a receive message buffer holds semantically valid frame data or not.
It is up to the host to reset this bit during the configuration state. It changes to ‘1’ when the first valid non
null frame is received.
1 – The corresponding buffer contains semantically valid frame data.
0 – The corresponding buffer does not contain semantically valid frame data.
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Sets the appropriate VALID bit — valid data frame.
Clears the VALID bit when the frame has been transmitted, if the appropriate TT bit of the buffer
is clear (event type of transmission).
Does not change the VALID bit when the frame has been transmitted, if the appropriate TT bit of
the buffer is set (state type of transmission).
The TT bit controls how the CC operates with the VALID bit.
MFR4200 Data Sheet, Rev. 0
Message Buffer Control, Configuration, Status and Filtering Register Set
NOTE
Register”) and unlocked it, the
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