Enhanced Serial Communication Interface (eSCI)
MPC5565 Microcontroller Reference Manual, Rev. 1.0
Freescale Semiconductor
20-39
Refer to
for more information.
Figure 20-25. DMA Transfer of a TX frame
20.4.10.3 Generating an RX Frame
For RX frames the header information is provided by the LIN master. The data, CRC and checksum bytes
(as enabled) are provided by the LIN slave. The LIN master verifies CRC and checksum bytes transmitted
by the slave.
For an RX frame, control information must be written to the ESCI
x
_LTR in the same manner as for the
TX frames. Additionally the timeout bits, which define the time to complete the entire frame, must be
written. Then the ESCI
x
_SR[RXRDY] bit must be checked (either with an interrupt, RX DMA interface,
or by polling) to detect incoming data bytes. The checksum byte normally does not appear in the
ESCI
x
_LRR, instead the LIN hardware verifies the checksum and issue an interrupt, if the checksum value
is not correct.
Two DMA channels can be used when executing an RX frame: one to transfer the header/control
information from a memory location to the ESCI
x
_LTR, and one to transfer the incoming data bytes from
the ESCI
x
_LRR to a table in memory. After the last byte from the RX frame has been stored, the DMA
controller can indicate completion to the CPU.
NOTE
It is also possible to setup a whole sequence of RX and TX frames, and
generate a single event at the end of that sequence.
Break
Sync
ID
Data
Data
CSum
• • •
LIN Frame
LIN eSCI
ESCI
x
_LTR
DMA
Controller
Data
n
Data 1
Control/Timeout
Length
ID
•
•
•
TX DMA
Channel
Summary of Contents for MPC5565
Page 18: ...MPC5565 Microcontroller Reference Manual Devices Supported MPC5565 MPC5565 RM Rev 1 0 09 2007...
Page 34: ...MPC5565 Reference Manual Rev 1 0 Freescale Semiconductor 15...
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Page 553: ...Flash Memory MPC5565 Microcontroller Reference Manual Rev 1 0 13 38 Freescale Semiconductor...
Page 559: ...SRAM MPC5565 Microcontroller Reference Manual Rev 1 0 14 6 Freescale Semiconductor...
Page 973: ...Preface MPC5565 Microcontroller Reference Manual Rev 1 0 21 36 Freescale Semiconductor...
Page 1153: ...Calibration MPC5565 Microcontroller Reference Manual Rev 1 0 B 8 Freescale Semiconductor...