SC9S12XS256J1MAA FREESCALE [Freescale Semiconductor, Inc], SC9S12XS256J1MAA Datasheet - Page 424

• Manufacturer Part Number: SC9S12XS256J1MAA
• Description: HCS12 Microcontrollers
• Manufacturer: FREESCALE [Freescale Semiconductor, Inc]

Serial Communication Interface (S12SCIV5)
In
at RT5 is high. The RT5 sample sets the noise flag. Although this is a worst-case misalignment of perceived
bit time, the data samples RT8, RT9, and RT10 are within the bit time and data recovery is successful.
Figure 14-25
synchronization with the start bit time, it does set the noise flag.
424
Figure
RT Clock Count
Reset RT Clock
RT Clock Count
Reset RT Clock
RT Clock
RT Clock
Samples
Samples
14-24, a large burst of noise is perceived as the beginning of a start bit, although the test sample
RXD
RXD
shows the effect of noise early in the start bit time. Although this noise does not affect proper
1
1
1
1
1
1
1
0
1
Figure 14-24. Start Bit Search Example 3
Figure 14-25. Start Bit Search Example 4
1
0
S12XS Family Reference Manual, Rev. 1.09
1
1
1
1
Perceived Start Bit
0
0
0
1
0
0
Perceived and Actual Start Bit
0
Actual Start Bit
Freescale Semiconductor
LSB
LSB