Receiver
MSC8144E Reference Manual, Rev. 3
Freescale Semiconductor
20-15
In Figure 20-11, the verification sample at RT3 is high. The RT3 sample sets the noise flag.
Although the perceived bit time is misaligned, the data samples RT8, RT9, and RT10 of the next
bit are within the bit time and data recovery is successful.
In Figure 20-12 the first start bit verification is a case similar to that in Figure 20-10, Start Bit
Search Example 1, but this time the first logic 0 detected is the real beginning of start bit. The
noise is at samples R3 and R5 which causes the RT counter to reset and the start bit search begins
again. Although the perceived bit time is misaligned, the data samples RT8, RT9, and RT10 of
the next bit are within the bit time and data recovery is successful. For this case the noise and
framing error flags are not set.
Figure 20-11. Start Bit Search Example 2
Figure 20-12. Start Bit Search Example 3
RT
1
RT
1
RT
1
RT
1
RT
1
RT
1
RT
2
RT
3
RT
4
RT
5
RT
6
RT
7
RT
8
RT
1
1
RT
1
0
RT
9
RT
1
4
RT
1
3
RT
1
2
RT
2
RT
1
RT
1
6
RT
1
5
RT
3
RT
4
RT
5
RT
6
RT
7
Actual Start Bit
1
1
1
1
1
1
0 0
0
0
LSB
0
0
Perceived Start Bit
Reset RT Counter
Samples
RT Clock
RT Clock Count
URXD
Reset RT Counter
RT1
RT1
RT1
RT1
RT2
RT3
RT4
RT5
RT1
RT2
RT3
RT4
RT5
RT8
RT7
RT6
RT
1
1
RT
1
0
RT9
RT
1
5
RT
1
4
RT
1
3
RT
1
2
RT
1
6
RT1
RT2
RT3
RT4
Samples
RT Clock
RT Clock Count
Actual Start Bit
URXD
1
0
1
1
1
0
0
LSB
1
Perceived Start Bit
0
0
0
RT
5
RT
6
RT
7
RT
8
RT
9
RT
1
0
0 0 0
Summary of Contents for MSC8144E
Page 1: ...MSC8144E Reference Manual Quad Core Media Signal Processor MSC8144ERM Rev 3 July 2009 ...
Page 48: ...MSC8144E Reference Manual Rev 3 xlviii Freescale Semiconductor ...
Page 86: ...MSC8144E Reference Manual Rev 3 1 38 Freescale Semiconductor Overview ...
Page 168: ...MSC8144E Reference Manual Rev 3 3 60 Freescale Semiconductor External Signals ...
Page 242: ...MSC8144E Reference Manual Rev 3 5 26 Freescale Semiconductor Reset ...
Page 314: ...MSC8144E Reference Manual Rev 3 8 24 Freescale Semiconductor General Configuration Registers ...
Page 414: ...MSC8144E Reference Manual Rev 3 10 14 Freescale Semiconductor MSC8144E SC3400 DSP Subsystem ...
Page 452: ...MSC8144E Reference Manual Rev 3 11 38 Freescale Semiconductor Internal Memory Subsystem ...
Page 520: ...MSC8144E Reference Manual Rev 3 12 68 Freescale Semiconductor DDR SDRAM Memory Controller ...
Page 1070: ...MSC8144E Reference Manual Rev 3 21 28 Freescale Semiconductor Timers ...