PXD10RM Datasheet, PDF (874/1332 Pages) Freescale Semiconductor, Inc – PXD10 Microcontroller

LINSR is set once the first 8 bytes have been transmitted. The application has to update the buffer BDR
before resetting the DBEF bit. The transmission of the next bytes starts when the DBEF bit is reset.
Once the last data byte (or the checksum byte) has been sent, the DTF flag is set.
The direction of the message buffer is controlled by the DIR bit in the BIDR. When the application sets
this bit the response is sent by LINFlex (publisher). Resetting this bit configures the message buffer as
subscriber.
23.8.2.1.3 Data reception (transceiver as subscriber)
To receive data from a slave node, the master sends a header with the corresponding identifier. LINFlex
stores the data received from the slave in the message buffer and stores the message status in the LINSR.
If the response has been received successfully, the DRF bit in the LINSR is set. In case of error, the DRF
flag is not set and the corresponding error flag is set in the LINESR (refer to Section 23.8.2.1.6, Error
handling).
It is possible to handle frames with a Response size larger than 8 bytes of data (extended frames). If the
data field length in the BIDR is configured with a value higher than 8 data bytes, the DBFF bit in the
LINSR is set once the first 8 bytes have been received. The application has to read the buffer BDR before
resetting the DBFF bit. Once the last data byte (or the checksum byte) has been received, the DRF flag is
set.
23.8.2.1.4 Data discard
To discard data from a slave, the DIR bit in the BIDR must be reset and the DDRQ bit in LINCR2 must
be set before starting the header transmission.
23.8.2.1.5 Error detection
LINFlex is able to detect and handle LIN communication errors. A code stored in the LIN error status
register (LINESR) signals the errors to the software.
In Master mode, the following errors are detected:
• Bit error: During transmission, the value read back from the bus differs from the transmitted value.
• Framing error: A dominant state has been sampled on the stop bit of the currently received
character (synch field, identifier field or data field).
• Checksum error: The computed checksum does not match the received one.
• Response and Frame timeout: Refer to Section 23.8.3, 8-bit timeout counter for more details.
23.8.2.1.6 Error handling
In case of Bit Error detection during transmission, LINFlex stops the transmission of the frame after the
corrupted bit. LINFlex returns to idle state and an interrupt is generated if the BEIE bit in the LINIER is set.
During reception, a Framing Error leads LINFlex to discard the current frame. LINFlex returns
immediately to idle state. An interrupt is generated if the FEIE bit in the LINIER is set.
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PXD10 Microcontroller Reference Manual, Rev. 1
Preliminary—Subject to Change Without Notice
Freescale Semiconductor