mc68hc908ap8cfa Freescale Semiconductor, Inc, mc68hc908ap8cfa Datasheet - Page 163

• Manufacturer Part Number: mc68hc908ap8cfa
• Description: M68hc08 Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

Start bit verification is not successful if any two of the three verification samples are logic 1s. 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.
To verify a stop bit and to detect noise, recovery logic takes samples at RT8, RT9, and RT10.
summarizes the results of the stop bit samples.
Freescale Semiconductor
Table 11-3
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 logic 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.
RT8, RT9, and RT10
RT8, RT9, and RT10
Samples
Samples
000
001
010
011
100
101
110
111
MC68HC908AP Family Data Sheet, Rev. 4
000
001
010
011
100
101
110
111
Table 11-4. Stop Bit Recovery
Table 11-3. Data Bit Recovery
NOTE
Determination
Error Flag
Data Bit
Framing
0
0
0
1
0
1
1
1
1
1
1
0
1
0
0
0
Noise Flag
Noise Flag
0
1
1
1
1
1
1
0
0
1
1
1
1
1
1
0
Functional Description
Table 11-4
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