Enhanced Modular Input/Output Subsystem (eMIOS200)
Freescale Semiconductor
23-67
PXR40 Microcontroller Reference Manual, Rev. 1
Figure 23-61. Time Base Period when Running in the Fastest Prescaler Ratio
If the prescaler ratio is greater than one or external clock is selected, the counter may behave in three
different ways depending on the channel mode:
•
If MC mode and Clear on Match Start and External Clock source are selected the internal counter
behaves as described in
.
•
If MC mode and Clear on Match Start and Internal Clock source are selected the internal counter
behaves as described in
.
•
If MC mode and Clear on Match End are selected the internal counter behaves as described in
.
•
If OPWFM mode is selected the internal counter behaves as described in
. The
internal counter clears at the start of the match signal, skips the next prescaled clock edge and then
increments in the subsequent prescaled clock edge.
NOTE
MCB and OPWFMB modes have a different behavior.
Figure 23-62. Time Base Period when Running with a Prescaler Ratio Greater Than 1
When a match occurs, the first clock cycle is used to clear the internal counter,
starting another period.
Note:
Prescaled Clock = 1
Internal Counter
1
2
3
0
1
2
3
0
1
2
3
0
1
2
3
0
1
2
3
0
1
2
3
Match Value = 3
Clock
See Note
PRESCALED CLOCK RATIO = 1 (Bypassed)
When a match occurs, the first clock cycle is used to clear the internal counter, and only
after a second edge of prescaled clock the counter will start counting.
Note:
Prescaled Clock
Internal Counter
1
2
0
Match Value = 3
Clock
See Note
3
1
2
3
0
0
0
PRESCALED CLOCK RATIO = 3
Summary of Contents for PXR4030
Page 1: ...PXR40 Microcontroller Reference Manual Devices Supported PXR4030 PXR4040 PXR40RM Rev 1 06 2011...
Page 30: ...PXR40 Microcontroller Reference Manual Rev 1 Freescale Semiconductor xxx...
Page 40: ...PXR40 Microcontroller Reference Manual Rev 1 xl Freescale Semiconductor...
Page 66: ...Memory Map PXR40 Microcontroller Reference Manual Rev 1 2 4 Freescale Semiconductor...
Page 120: ...Signal Descriptions 3 54 Freescale Semiconductor PXR40 Microcontroller Reference Manual Rev 1...
Page 860: ...FlexCAN Module 24 50 Freescale Semiconductor PXR40 Microcontroller Reference Manual Rev 1...
Page 1167: ...Decimation Filter Freescale Semiconductor 28 53 PXR40 Microcontroller Reference Manual Rev 1...
Page 1168: ...Decimation Filter 28 54 Freescale Semiconductor PXR40 Microcontroller Reference Manual Rev 1...
