Enhanced Serial Communication Interface (eSCI)
26-40
Freescale Semiconductor
PXR40 Microcontroller Reference Manual, Rev. 1
26.4.5.3.17
Data Bit Synchronization
To adjust for baud rate mismatch during the reception of data bits, the cyclic sample counter RSC can be
configured to be synchronized on falling edges during data bit reception. This kind of synchronization is
performed only if the synchronization mode bit SYNM in the
is 0.
Data Bit Synchronization (Right Shifted Edges)
This kind of sample counter synchronization happens if the transmitter is slower than the receiver. The
reset behavior of the sample counter is shown in
. The sample counter reset condition is:
1. The data bit N-1 is sampled as 1, and
2. the data bit N is sampled as 0, and
3. a falling edge consisting of three consecutive 1-samples and a following 0-sample is detected, and
4. the 0-sample of the falling edge is received at data bit N sample j, with 1 <= j <= 8.
If the condition is fulfilled, the sample counter is reset 16 RCLK cycles after the 0 of the falling edge
condition was received. The bit counter is not increased.
Figure 26-34. Data Bit Synchronization (Right Shifted Edges)
Data Bit Synchronization (Left Shifted Edges)
This kind of sample counter synchronization happens if the transmitter is faster than the receiver. The reset
behavior of the sample counter is shown in
. The sample counter reset condition is:
1. The data bit N-1 is sampled as 1, and
2. the data bit N is sampled as 0, and
3. a falling edge consisting of three consecutive 1-samples and a following 0-sample is detected, and
4. the 0-sample of the falling edge is received at data bit N sample j, with 11 <= j <= 16.
If the condition is fulfilled, the sample counter is reset 16 RCLK cycles after the 0-sample of the falling
edge condition was received. The bit counter is increased by 1.
VOTING
DATA
RCLK
RXD
2 3
RSC
4 5 6 7 8 9 10 11 12 13 14 15 16
1 2
wrap
1
wrap
3
sample counter reset
right shifted falling edge
FALLING
EDGE
2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
1
2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
1
VOTING
DATA
reset
VOTING
DATA
DATA BIT N-1
DATA BIT N
DATA BIT N+1
Summary of Contents for PXR4030
Page 1: ...PXR40 Microcontroller Reference Manual Devices Supported PXR4030 PXR4040 PXR40RM Rev 1 06 2011...
Page 30: ...PXR40 Microcontroller Reference Manual Rev 1 Freescale Semiconductor xxx...
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Page 66: ...Memory Map PXR40 Microcontroller Reference Manual Rev 1 2 4 Freescale Semiconductor...
Page 120: ...Signal Descriptions 3 54 Freescale Semiconductor PXR40 Microcontroller Reference Manual Rev 1...
Page 860: ...FlexCAN Module 24 50 Freescale Semiconductor PXR40 Microcontroller Reference Manual Rev 1...
Page 1167: ...Decimation Filter Freescale Semiconductor 28 53 PXR40 Microcontroller Reference Manual Rev 1...
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