PRS - Peripheral Reflex System#

PRS_ChType_t#

PRS_ChType_t

PRS Channel type.

PRS_Edge_TypeDef#

PRS_Edge_TypeDef

Edge detection type.

PRS_Logic_t#

PRS_Logic_t

Logic functions that can be used when combining two PRS channels.

PRS_Signal_t#

PRS_Signal_t

PRS Signal.

PRS_Consumer_t#

PRS_Consumer_t

PRS Consumers.

PRS_LevelSet#

void PRS_LevelSet (uint32_t level, uint32_t mask)

Set level control bit for one or more channels.

The level value for a channel is XORed with both the pulse possibly issued by PRS_PulseTrigger() and the PRS input signal selected for the channel(s).

Note

• Note that software level control is only available for asynchronous channels on Series 2 devices.

PRS_LevelGet#

uint32_t PRS_LevelGet (void )

Get level control bit for all channels.

Returns

• The current software level configuration.

PRS_Values#

uint32_t PRS_Values (PRS_ChType_t type)

Get the PRS channel values for all channels.

Returns

• The current PRS channel output values for all channels as a bitset.

PRS_ChannelValue#

bool PRS_ChannelValue (unsigned int ch, PRS_ChType_t type)

Get the PRS channel value for a single channel.

Returns

• The current PRS channel output value. This is either 0 or 1.

PRS_PulseTrigger#

void PRS_PulseTrigger (uint32_t channels)

Trigger a high pulse (one HFPERCLK) for one or more channels.

Setting a bit for a channel causes the bit in the register to remain high for one HFPERCLK cycle. Pulse is XORed with both the corresponding bit in PRS SWLEVEL register and the PRS input signal selected for the channel(s).

PRS_ChannelLevelSet#

void PRS_ChannelLevelSet (unsigned int ch, bool level)

Set the PRS channel level for one asynchronous PRS channel.

PRS_ChannelPulse#

void PRS_ChannelPulse (unsigned int ch)

Trigger a pulse on one PRS channel.

PRS_SourceSignalSet#

void PRS_SourceSignalSet (unsigned int ch, uint32_t source, uint32_t signal, PRS_Edge_TypeDef edge)

Set a source and signal for a channel.

PRS_SourceAsyncSignalSet#

void PRS_SourceAsyncSignalSet (unsigned int ch, uint32_t source, uint32_t signal)

Set the source and asynchronous signal for a channel.

Asynchronous reflexes are not clocked on HFPERCLK and can be used even in EM2/EM3. There is a limitation to reflexes operating in asynchronous mode in that they can only be used by a subset of the reflex consumers. See the PRS chapter in the reference manual for the complete list of supported asynchronous signals and consumers.

Note

• This function is not supported on EFM32GxxxFyyy parts. In asynchronous mode, the edge detector only works in EM0 and should not be used. The EDSEL parameter in PRS_CHx_CTRL register is set to 0 (OFF) by default.

PRS_GetFreeChannel#

int PRS_GetFreeChannel (PRS_ChType_t type)

Search for the first free PRS channel.

Returns

• Channel number >= 0 if an unused PRS channel was found. If no free PRS channel was found then -1 is returned.

PRS_Reset#

void PRS_Reset (void )

Reset all PRS channels.

This function will reset all the PRS channel configuration.

PRS_ConnectSignal#

void PRS_ConnectSignal (unsigned int ch, PRS_ChType_t type, PRS_Signal_t signal)

Connect a PRS signal to a channel.

This function will make the PRS signal available on the specific channel. Only a single PRS signal can be connected to any given channel.

PRS_ConvertToSyncSource#

uint32_t PRS_ConvertToSyncSource (uint32_t asyncSource)

Convert an async PRS source to a sync source.

This conversion must be done because the id's of the same peripheral source is different depending on if it's used as an asynchronous PRS source or a synchronous PRS source.

Returns

• The id of the corresponding synchronous PRS source.

PRS_ConvertToSyncSignal#

uint32_t PRS_ConvertToSyncSignal (uint32_t asyncSource, uint32_t asyncSignal)

Convert an async PRS signal to a sync signal.

PRS values for some peripherals signals differ between asynchronous and synchronous PRS channels. This function must be used to handle the conversion.

Returns

• The id of the corresponding synchronous PRS signal.

PRS_ConnectConsumer#

void PRS_ConnectConsumer (unsigned int ch, PRS_ChType_t type, PRS_Consumer_t consumer)

Connect a peripheral consumer to a PRS channel.

Different peripherals can use PRS channels as their input. This function can be used to connect a peripheral consumer to a PRS channel. Multiple consumers can be connected to a single PRS channel.

PRS_PinOutput#

void PRS_PinOutput (unsigned int ch, PRS_ChType_t type, GPIO_Port_TypeDef port, uint8_t pin)

Send the output of a PRS channel to a GPIO pin.

This function is used to send the output of a PRS channel to a GPIO pin. Note that there are certain restrictions to where a PRS channel can be routed. Consult the datasheet of the device to see if a channel can be routed to the requested GPIO pin. Some devices for instance can only route the async channels 0-5 on GPIO pins PAx and PBx while async channels 6-11 can only be routed to GPIO pins PCx and PDx

PRS_Combine#

void PRS_Combine (unsigned int chA, unsigned int chB, PRS_Logic_t logic)

Combine two PRS channels using a logic function.

This function allows you to combine the output of one PRS channel with the the signal of another PRS channel using various logic functions. Note that for series 2, config 1 devices, the hardware only allows a PRS channel to be combined with the previous channel. So for instance channel 5 can be combined only with channel 4.

The logic function operates on two PRS channels called A and B. The output of PRS channel B is combined with the PRS source configured for channel A to produce an output. This output is used as the output of channel A.

PRS_SYNC_CHAN_COUNT#

#define PRS_SYNC_CHAN_COUNT

PRS_SYNC_CH_NUM

PRS Synchronous channel count.

PRS_ASYNC_CHAN_COUNT#

#define PRS_ASYNC_CHAN_COUNT

PRS_ASYNC_CH_NUM

PRS Asynchronous channel count.

PRS_ASYNC_SUPPORTED#

#define PRS_ASYNC_SUPPORTED

1

PRS asynchronous support.