mc9s12xs128 Freescale Semiconductor, Inc, mc9s12xs128 Datasheet - Page 425

• Manufacturer Part Number: mc9s12xs128
• Description: Hcs12 Microcontrollers 16-bit Automotive Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

In
not the beginning of a start bit. The RT clock is reset and the start bit search begins again. The noise flag
is not set because the noise occurred before the start bit was found.
In
perceived bit time is misaligned, the data samples RT8, RT9, and RT10 are within the bit time and data
recovery is successful.
Freescale Semiconductor
Figure 14-22
Figure
RT Clock Count
Reset RT Clock
RT Clock Count
Reset RT Clock
RT Clock
RT Clock
Samples
Samples
14-23, verification sample at RT3 is high. The RT3 sample sets the noise flag. Although the
RXD
RXD
the verification samples RT3 and RT5 determine that the first low detected was noise and
1
1
1
1
1
1
1
0
1
Figure 14-22. Start Bit Search Example 1
Figure 14-23. Start Bit Search Example 2
0
1
S12XS Family Reference Manual, Rev. 1.10
1
1
1
0
0
Perceived Start Bit
0
0
0
0
0
0
Actual Start Bit
Start Bit
0
0
0
Serial Communication Interface (S12SCIV5)
0
LSB
LSB
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