mc9s12vr48 Freescale Semiconductor, Inc, mc9s12vr48 Datasheet - Page 336

• Manufacturer Part Number: mc9s12vr48
• Description: S12 Microcontrollers
• Manufacturer: 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 10-25
synchronization with the start bit time, it does set the noise flag.
336
Figure
RT Clock Count
Reset RT Clock
RT Clock Count
Reset RT Clock
RT Clock
RT Clock
Samples
Samples
10-24, 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
MC9S12VR Family Reference Manual,
Figure 10-24. Start Bit Search Example 3
Figure 10-25. Start Bit Search Example 4
1
Preliminary - Subject to Change Without Notice
0
1
1
1
1
Perceived Start Bit
0
0
0
1
0
0
Perceived and Actual Start Bit
0
Actual Start Bit
Rev. 2.2
Freescale Semiconductor
LSB
LSB