MC9S12Q FREESCALE [Freescale Semiconductor, Inc], MC9S12Q Datasheet - Page 401

• Manufacturer Part Number: MC9S12Q
• Description: Microcontrollers
• Manufacturer: FREESCALE [Freescale Semiconductor, Inc]

Figure 13-18
after the reset is low but is not preceded by three high samples that would qualify as a falling edge.
Depending on the timing of the start bit search and on the data, the frame may be missed entirely or it may
set the framing error flag.
In
noise flag but does not reset the RT clock. In start bits only, the RT8, RT9, and RT10 data samples are
ignored.
Freescale Semiconductor
Figure
RT CLOCK COUNT
RT CLOCK COUNT
RESET RT CLOCK
RESET RT CLOCK
Rx Input Signal
Rx Input Signal
RT CLOCK
RT CLOCK
SAMPLES
SAMPLES
13-19, a noise burst makes the majority of data samples RT8, RT9, and RT10 high. This sets the
shows a burst of noise near the beginning of the start bit that resets the RT clock. The sample
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Figure 13-18. Start Bit Search Example 5
Figure 13-19. Start Bit Search Example 6
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Chapter 13 Serial Communications Interface (S12SCIV2) Block Description
MC9S12Q128
Rev 1.09
0
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0
START BIT
START BIT
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1
NO START BIT FOUND
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LSB
LSB
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