PXN20RM Datasheet, PDF (1028/1376 Pages) Freescale Semiconductor, Inc – PXN20 Microcontroller

Enhanced Serial Communication Interface (eSCI)
Table 31-29. Start Bit Verification (continued)Result
[RS3, RS5, RS7]
100
011
101
110
111
Start Bit Verified
Yes
No
No
No
No
Noise Detected
Yes
No
No
No
No
If the start bit verification was not successful, the receiver resumes the start bit qualification. If the start bit
verification was successful, the receiver continues sampling to perform noise detection on the samples at
RS8, RS9, and RS10. The results of the start bit noise detection is summarized in Table 31-30.
Table 31-30. Start Bit Noise Detection
[RS8, RS9, RS10]
000
001
010
100
011
101
110
111
Noise Detected
No
Yes
Yes
Yes
Yes
Yes
Yes
Yes
31.4.5.3.16 Data Bit Sampling
Receiver Input
DATA / STOP BIT
Sampled Value 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1
DATA
VOTING
RCLK
RSC 12 13 14 15 16 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 1 2
sample counter wrap
data strobing
Figure 31-33. Data and Stop Bit Sampling and Strobing
sample counter wrap
To determine the value of a data bit and to detect noise, a two out of three majority voting is performed on
the samples RS8, RS9, and RS10. Table 31-31 summarizes the results of the data bit sample. The receiver
detects the number of data bit according to the selected frame format.
31-38
PXN20 Microcontroller Reference Manual, Rev. 1
Freescale Semiconductor