mc9s12e256 Freescale Semiconductor, Inc, mc9s12e256 Datasheet - Page 267

• Manufacturer Part Number: mc9s12e256
• Description: Hcs12 Microcontrollers 16-bit Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

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 8-19
synchronization with the start bit time, it does set the noise flag.
Freescale Semiconductor
RT CLOCK COUNT
RT CLOCK COUNT
RESET RT CLOCK
RESET RT CLOCK
Figure
RT CLOCK
RT CLOCK
SAMPLES
SAMPLES
8-18, a large burst of noise is perceived as the beginning of a start bit, although the test sample
shows the effect of noise early in the start bit time. Although this noise does not affect proper
RXD
RXD
1
1
1
1
1
1
1
0
1
Figure 8-18. Start Bit Search Example 3
Figure 8-19. Start Bit Search Example 4
1
0
MC9S12E256 Data Sheet, Rev. 1.08
1
1
1
PERCEIVED START BIT
1
0
0
0
1
0
PERCEIVED AND ACTUAL START BIT
0
0
ACTUAL START BIT
Chapter 8 Serial Communication Interface (SCIV4)
LSB
LSB
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