mc68hc908kx8 Freescale Semiconductor, Inc, mc68hc908kx8 Datasheet - Page 120

• Manufacturer Part Number: mc68hc908kx8
• Description: M68hc08 Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

Serial Communications Interface Module (SCI)
To verify the start bit and to detect noise, data recovery logic takes samples at RT3, RT5, and RT7.
Table 12-2
If start bit verification is not successful, the RT clock is reset and a new search for a start bit begins.
To determine the value of a data bit and to detect noise, recovery logic takes samples at RT8, RT9, and
RT10.
120
Table 12-3
summarizes the results of the start bit verification samples.
The RT8, RT9, and RT10 samples do not affect start bit verification. If any
or all of the RT8, RT9, and RT10 start bit samples are 1s following a
successful start bit verification, the noise flag (NF) is set and the receiver
assumes that the bit is a start bit.
summarizes the results of the data bit samples.
MC68HC908KX8 • MC68HC908KX2 • MC68HC08KX8 Data Sheet, Rev. 2.1
and RT10 Samples
and RT7 Samples
RT8, RT9,
RT3, RT5,
000
001
010
011
100
101
110
111
000
001
010
011
100
101
110
111
Table 12-2. Start Bit Verification
Table 12-3. Data Bit Recovery
NOTE
Determination
Verification
Start Bit
Data Bit
Yes
Yes
Yes
Yes
No
No
No
No
0
0
0
1
0
1
1
1
Noise Flag
Noise Flag
0
1
1
0
1
0
0
0
0
1
1
1
1
1
1
0
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