Periodic Interrupt Timer (PIT_RTI)
20-8
Freescale Semiconductor
PXR40 Microcontroller Reference Manual, Rev. 1
The counter period can be restarted, by first disabling, then enabling the timer with the TEN bit (see
).
The counter period of a running timer can be modified, by first disabling the timer, setting a new load value
and then enabling the timer again (see
). In the case of the RTI, because of the different clock
domains (system clock / oscillator clock), a delay must be respected between setting the new value and
re-enabling the RTI.
It is also possible to change the counter period without restarting the timer by writing the LDVAL register
with the new load value. This value is loaded after the next trigger (counter reaches 0) event (see
).
Figure 20-7. Stopping and Starting a Timer
Figure 20-8. Modifying Running Timer Period
Figure 20-9. Dynamically Setting a New Load Value
20.4.1.2
Debug Mode
In debug mode the timers may be configured to stop when the debugger halts the device. This is intended
to aid software development, allowing the developer to halt the processor, investigate the current state of
the system (e.g. the timer values) and then continue the operation.
p1
p1
Timer Enabled
Disable
Timer
p1
Start Value = p1
Trigger
Event
p1
Re-Enable
Timer
p1
Timer Enabled
Disable
Timer,
Start Value = p1
Trigger
Event
Re-Enable
Timer
p1
Set new
Load Value
p2
p2
p2
p1
p1
Timer Enabled
New Start
Value p2 set
p1
p2
Start Value = p1
p2
Trigger
Event
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...
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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...
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