MCCIRM Freescale Semiconductor / Motorola, MCCIRM Datasheet - Page 81

• Manufacturer Part Number: MCCIRM
• Description: MCCIRM Multi-Channel Communications Interface Reference Manual
• Manufacturer: Freescale Semiconductor / Motorola

Multichannel Communication Interface — Rev. 1.0
MOTOROLA
Figure 5-7
Although this noise does not affect proper synchronization with the start
bit time, it does set the internal noise flag.
Figure 5-8
bit that causes the start bit search to be restarted. During RT1 following
RT7, a search for a new start bit could not be started as the previous
three RT samples are not all high. The receiver bit processor misses this
start bit. The frame might be partially received or missed entirely,
depending on the data in the frame and when the start bit search logic
synchronized upon what appeared to be a start bit. If a valid stop bit is
not detected, the FE flag is set in SCSR.
*
^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^
R
^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^
1
R
1
T
1
T
1
*
*
Freescale Semiconductor, Inc.
RESTART RT CLOCK
RESTART RT CLOCK
R
1
T
R
1
1
T
1
*
*
For More Information On This Product,
R
R
1
T
1
1
T
1
*
*
R
1
T
R
1
1
T
1
*
*
R
R
1
T
1
1
T
1
illustrates the effect of noise early within the start bit time.
shows a large burst of noise near the beginning of the start
*
*
Go to: www.freescale.com
R
1
T
R
1
1
T
1
*
*
R
R
1
T
1
T
1
1
*
*
Figure 5-7. Start Search Example 5
Figure 5-8. Start Search Example 6
SCI Submodule
R
1
T
R
1
1
T
1
*
*
R
R
1
T
1
1
T
1
*
*
R
0
T
1
R
0
T
1
R
R
T
2
T
2
R
1
T
3
R
0
T
3
SEE EXPLANATION – NO START BIT FOUND
R
R
T
4
T
4
R
0
T
5
R
1
T
5
PERCEIVED START BIT
R
R
T
6
0
T
6
ACTUAL START BIT
ACTUAL START BIT
R
0
T
R
7
1
T
7
*
R
R
0
T
8
0
T
1
*
R
0
T
R
9
0
T
1
*
R
R
0
T
1
0
0
T
1
*
R
T
R
1
1
0
T
1
*
R
T
1
2
R
0
T
1
*
R
T
1
3
R
0
T
1
*
R
R
T
1
4
0
T
1
*
Reference Manual
R
T
R
1
5
0
T
1
SCI Submodule
SCI Transmitter
*
R
R
T
1
6
0
T
1
*
*
R
T
R
1
T
1
*
R
R
T
T
2
1
LSB
LSB
*
R
T
3
R
T
1
81