Texas Instruments Tiva TM4C123GH6PM, User Manual

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Pulse Width Modulator (PWM)
Description:
Clears one or more fault interrupts by writing to the appropriate bit of the PWM interrupt status
register. The parameter
ui32FaultInts must be the logical OR of any of PWM_INT_FAULT0 ,
PWM_INT_FAULT1 , PWM_INT_FAULT2 , or PWM_INT_FAULT3 .
When running on a device supporting extended PWM fault handling, the fault interrupts are
derived by performing a logical OR of each of the configured fault trigger signals for a given
generator. Therefore, these interrupts are not directly related to the four possible FAULTn
inputs to the device but indicate that a fault has been signaled to one of the four possible PWM
generators. On a device without extended PWM fault handling, the interrupt is directly related
to the state of the single FAULT pin.
Note:
Because there is a write buffer in the Cortex-M4 processor, it may take several clock cycles
before the interrupt source is actually cleared. Therefore, it is recommended that the interrupt
source be cleared early in the interrupt handler (as opposed to the very last action) to avoid
returning from the interrupt handler before the interrupt source is actually cleared. Failure to
do so may result in the interrupt handler being immediately reentered (because the interrupt
controller still sees the interrupt source asserted).
Returns:
None.
15.2.1.5 ROM_PWMGenConfigure
Configures a PWM generator.
Prototype:
void
ROM_PWMGenConfigure(uint32_t ui32Base,
uint32_t ui32Gen,
uint32_t ui32Config)
ROM Location:
ROM_APITABLE
is an array of pointers located at
0x0100.0010
.
ROM_PWMTABLE
is an array of pointers located at
ROM_APITABLE[8]
.
ROM_PWMGenConfigure
is a function pointer located at
ROM_PWMTABLE[1]
.
Parameters:
ui32Base is the base address of the PWM module.
ui32Gen
is the PWM generator to configure. Must be one of
PWM_GEN_0
,
PWM_GEN_1
,
PWM_GEN_2
, or
PWM_GEN_3
.
ui32Config is the configuration for the PWM generator.
Description:
This function is used to set the mode of operation for a PWM generator. The counting mode,
synchronization mode, and debug behavior are all configured. After configuration, the genera-
tor is left in the disabled state.
A PWM generator can count in two different modes: count down mode or count up/down mode.
In count down mode, it will count from a value down to zero, and then reset to the preset value.
This will produce left-aligned PWM signals (that is the rising edge of the two PWM signals
produced by the generator will occur at the same time). In count up/down mode, it will count
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