BLE#

Accelerator routines for Bluetooth Low Energy (BLE).

The APIs in this module configure the radio for BLE operation and provide additional helper routines necessary for normal BLE send/receive that aren't available directly in RAIL. RAIL APIs should be used to set up the application. However, RAIL_ConfigChannels() and RAIL_ConfigRadio() should not be called to set up the PHY. Instead, RAIL_BLE_Config* APIs should be used to set up the 1 Mbps, 2 Mbps, or Coded PHY configurations needed by the application. These APIs will configure the hardware and also configure the set of valid BLE channels.

To implement a standard BLE link layer, you will also need to handle tight turnaround times and send packets at specific instants. This can all be managed through general RAIL functions, such as RAIL_ScheduleTx(), RAIL_ScheduleRx(), and RAIL_SetStateTiming(). See RAIL APIs for more useful functions.

A simple example to set up the application to be in BLE mode is shown below. Note that this will put the radio on the first advertising channel with the advertising Access Address. In any full-featured BLE application you will need to use the RAIL_BLE_ConfigChannelRadioParams() function to change the sync word and other parameters as needed based on your connection.

// RAIL Handle set at initialization time.
static RAIL_Handle_t gRailHandle = NULL;

static void radioEventHandler(RAIL_Handle_t railHandle,
                              RAIL_Events_t events)
{
  // ... handle RAIL events, e.g., receive and transmit completion
}

#if MULTIPROTOCOL
// Allocate memory for RAIL to hold BLE-specific state information
static RAIL_BLE_State_t bleState; // Must never be const
static RAILSched_Config_t schedCfg; // Must never be const
static RAIL_Config_t railCfg = {  // Must never be const
  .eventsCallback = &radioEventHandler,
  .protocol = &bleState, // For BLE, RAIL needs additional state memory
  .scheduler = &schedCfg, // For MultiProtocol, additional scheduler memory
};
#else
static RAIL_Config_t railCfg = {  // Must never be const
  .eventsCallback = &radioEventHandler,
  .protocol = NULL,
  .scheduler = NULL,
};
#endif

// Set the radio to receive on the first BLE advertising channel.
int bleAdvertiseEnable(void)
{
  // Initializes the RAIL library and any internal state it requires.
  gRailHandle = RAIL_Init(&railCfg, NULL);

  // Calls the BLE initialization function to load the right radio configuration.
  RAIL_BLE_Init(gRailHandle);

  // Always choose the Viterbi PHY configuration if available on your chip
  // for performance reasons.
  RAIL_BLE_ConfigPhy1MbpsViterbi(gRailHandle);

  // Configures us for the first advertising channel (Physical: 0, Logical: 37).
  // The CRC init value and Access Address come from the BLE specification.
  RAIL_BLE_ConfigChannelRadioParams(gRailHandle,
                                    0x555555,
                                    0x8E89BED6,
                                    37,
                                    false);

  // Starts receiving on physical channel 0 (logical channel 37).
  RAIL_StartRx(gRailHandle, 0, NULL);
 }

Modules#

RAIL_BLE_State_t

Angle of Arrival/Departure

BLE Radio Configurations

BLE TX Channel Hopping

Enumerations#

enum

RAIL_BLE_Coding_t {

RAIL_BLE_Coding_125kbps = 0

RAIL_BLE_Coding_125kbps_DSA = 1

RAIL_BLE_Coding_500kbps = 2

RAIL_BLE_Coding_500kbps_DSA = 3

}

The variant of the BLE Coded PHY.

enum

RAIL_BLE_Phy_t {

RAIL_BLE_1Mbps

RAIL_BLE_2Mbps

RAIL_BLE_Coded125kbps

RAIL_BLE_Coded500kbps

}

The variant of the BLE PHY.

enum

RAIL_BLE_SignalIdentifierMode_t {

RAIL_BLE_SIGNAL_IDENTIFIER_MODE_DISABLE = 0

RAIL_BLE_SIGNAL_IDENTIFIER_MODE_1MBPS

RAIL_BLE_SIGNAL_IDENTIFIER_MODE_2MBPS

}

Available Signal Identifier modes.

Functions#

RAIL_Status_t

RAIL_BLE_Init(RAIL_Handle_t railHandle)

Configure RAIL to run in BLE mode.

RAIL_Status_t

RAIL_BLE_Deinit(RAIL_Handle_t railHandle)

Take RAIL out of BLE mode.

bool

RAIL_BLE_IsEnabled(RAIL_Handle_t railHandle)

Determine whether BLE mode is enabled or not.

RAIL_Status_t

RAIL_BLE_ConfigPhyQuuppa(RAIL_Handle_t railHandle)

Switch to the 1 Mbps Quuppa PHY.

RAIL_Status_t

RAIL_BLE_ConfigPhy1MbpsViterbi(RAIL_Handle_t railHandle)

Switch to the Viterbi 1 Mbps BLE PHY.

RAIL_Status_t

RAIL_BLE_ConfigPhy1Mbps(RAIL_Handle_t railHandle)

Switch to the legacy non-Viterbi 1 Mbps BLE PHY.

RAIL_Status_t

RAIL_BLE_ConfigPhy2MbpsViterbi(RAIL_Handle_t railHandle)

Switch to the Viterbi 2 Mbps BLE PHY.

RAIL_Status_t

RAIL_BLE_ConfigPhy2Mbps(RAIL_Handle_t railHandle)

Switch to the legacy non-Viterbi 2 Mbps BLE PHY.

RAIL_Status_t

RAIL_BLE_ConfigPhyCoded(RAIL_Handle_t railHandle, RAIL_BLE_Coding_t bleCoding)

Switch to the BLE Coded PHY.

RAIL_Status_t

RAIL_BLE_ConfigPhySimulscan(RAIL_Handle_t railHandle)

Switch to the Simulscan PHY.

RAIL_Status_t

RAIL_BLE_ConfigChannelRadioParams(RAIL_Handle_t railHandle, uint32_t crcInit, uint32_t accessAddress, uint16_t channel, bool disableWhitening)

Change BLE radio parameters.

RAIL_Status_t

RAIL_BLE_PhySwitchToRx(RAIL_Handle_t railHandle, RAIL_BLE_Phy_t phy, uint16_t railChannel, uint32_t startRxTime, uint32_t crcInit, uint32_t accessAddress, uint16_t logicalChannel, bool disableWhitening)

Change the current BLE PHY and go into receive.

RAIL_Status_t

RAIL_BLE_ConfigSignalIdentifier(RAIL_Handle_t railHandle, RAIL_BLE_SignalIdentifierMode_t signalIdentifierMode)

Configure and enable signal identifier for BLE signal detection.

RAIL_Status_t

RAIL_BLE_EnableSignalDetection(RAIL_Handle_t railHandle, bool enable)

Enable or disable signal identifier interrupt for BLE signal detection.

Macros#

#define

RAIL_BLE_RX_SUBPHY_ID_500K (0U)

subPhyId indicating a 500kbps packet

#define

RAIL_BLE_RX_SUBPHY_ID_125K (1U)

subPhyId indicating a 125kbps packet

#define

RAIL_BLE_RX_SUBPHY_ID_1M (2U)

subPhyId value indicating a 1Mbps packet

#define

RAIL_BLE_RX_SUBPHY_ID_INVALID (3U)

Invalid subPhyId value.

#define

RAIL_BLE_RX_SUBPHY_COUNT (4U)

subPhyId indicating the total count

#define

RAIL_BLE_EnableSignalIdentifier RAIL_BLE_EnableSignalDetection

Backward compatible name for the RAIL_BLE_EnableSignalDetection API.

Enumeration Documentation#

RAIL_BLE_Coding_t#

RAIL_BLE_Coding_t

The variant of the BLE Coded PHY.

Enumerator
RAIL_BLE_Coding_125kbps	Enables the 125 kbps variant of the BLE Coded PHY.
RAIL_BLE_Coding_125kbps_DSA	DeprecatedWill be removed in a future version of RAIL
RAIL_BLE_Coding_500kbps	Enables the 500 kbps variant of the BLE Coded PHY.
RAIL_BLE_Coding_500kbps_DSA	DeprecatedWill be removed in a future version of RAIL

RAIL_BLE_Phy_t#

RAIL_BLE_Phy_t

The variant of the BLE PHY.

Enumerator
RAIL_BLE_1Mbps	Use the standard BLE 1Mbps PHY.
RAIL_BLE_2Mbps	Use the high data rate BLE 2Mbps PHY.
RAIL_BLE_Coded125kbps	Enables the 125 kbps variant of the BLE Coded PHY.
RAIL_BLE_Coded500kbps	Enables the 500 kbps variant of the BLE Coded PHY.

RAIL_BLE_SignalIdentifierMode_t#

RAIL_BLE_SignalIdentifierMode_t

Available Signal Identifier modes.

Enumerator
RAIL_BLE_SIGNAL_IDENTIFIER_MODE_DISABLE
RAIL_BLE_SIGNAL_IDENTIFIER_MODE_1MBPS
RAIL_BLE_SIGNAL_IDENTIFIER_MODE_2MBPS

Function Documentation#

RAIL_BLE_Init#

RAIL_Status_t RAIL_BLE_Init (RAIL_Handle_t railHandle)

Configure RAIL to run in BLE mode.

Parameters

Type	Direction	Argument Name	Description
RAIL_Handle_t	[in]	railHandle	A handle for RAIL instance.

Returns

Status code indicating success of the function call.

This function changes your radio, channel configuration, and other parameters to match what is needed for BLE, initially establishing the BLE 1mbps PHY. To switch back to a default RAIL mode, call RAIL_BLE_Deinit() first. This function will configure the protocol output on PTI to RAIL_PTI_PROTOCOL_BLE.

Note

BLE may not be enabled while Auto-ACKing is enabled.

RAIL_BLE_Deinit#

RAIL_Status_t RAIL_BLE_Deinit (RAIL_Handle_t railHandle)

Take RAIL out of BLE mode.

Parameters

Type	Direction	Argument Name	Description
RAIL_Handle_t	[in]	railHandle	A handle for RAIL instance.

Returns

Status code indicating success of the function call.

This function will undo some of the configuration that happens when you call RAIL_BLE_Init(). After this you can safely run your normal radio initialization code to use a non-BLE configuration. This function does not change back your radio or channel configurations so you must do this by manually reinitializing. This also resets the protocol output on PTI to RAIL_PTI_PROTOCOL_CUSTOM.

RAIL_BLE_IsEnabled#

bool RAIL_BLE_IsEnabled (RAIL_Handle_t railHandle)

Determine whether BLE mode is enabled or not.

Parameters

Type	Direction	Argument Name	Description
RAIL_Handle_t	[in]	railHandle	A handle for RAIL instance.

Returns

true if BLE mode is enabled and false otherwise.

This function returns the current status of RAIL's BLE mode. It is enabled by a call to RAIL_BLE_Init() and disabled by a call to RAIL_BLE_Deinit().

RAIL_BLE_ConfigPhyQuuppa#

RAIL_Status_t RAIL_BLE_ConfigPhyQuuppa (RAIL_Handle_t railHandle)

Switch to the 1 Mbps Quuppa PHY.

Parameters

Type	Direction	Argument Name	Description
RAIL_Handle_t	[in]	railHandle	A handle for RAIL instance.

Returns

Status code indicating success of the function call.

You can use this function to switch to the Quuppa PHY.

Note

Not all chips support the 1Mbps Quuppa PHY. This API should return RAIL_STATUS_INVALID_CALL if unsupported by the hardware we're building for.

RAIL_BLE_ConfigPhy1MbpsViterbi#

RAIL_Status_t RAIL_BLE_ConfigPhy1MbpsViterbi (RAIL_Handle_t railHandle)

Switch to the Viterbi 1 Mbps BLE PHY.

Parameters

Type	Direction	Argument Name	Description
RAIL_Handle_t	[in]	railHandle	A handle for RAIL instance.

Returns

A status code indicating success of the function call.

Use this function to switch back to the default BLE 1 Mbps PHY if you have switched to the 2 Mbps or another configuration. You may only call this function after initializing BLE and while the radio is idle.

RAIL_BLE_ConfigPhy1Mbps#

RAIL_Status_t RAIL_BLE_ConfigPhy1Mbps (RAIL_Handle_t railHandle)

Switch to the legacy non-Viterbi 1 Mbps BLE PHY.

Parameters

Type	Direction	Argument Name	Description
RAIL_Handle_t	[in]	railHandle	A handle for RAIL instance.

Returns

A status code indicating success of the function call.

Use this function to switch back to the legacy BLE 1 Mbps PHY if you have switched to the 2 Mbps or another configuration. You may only call this function after initializing BLE and while the radio is idle.

Note

The EFR32XG2x family does not support BLE non-Viterbi PHYs.

RAIL_BLE_ConfigPhy2MbpsViterbi#

RAIL_Status_t RAIL_BLE_ConfigPhy2MbpsViterbi (RAIL_Handle_t railHandle)

Switch to the Viterbi 2 Mbps BLE PHY.

Parameters

Type	Direction	Argument Name	Description
RAIL_Handle_t	[in]	railHandle	A handle for RAIL instance.

Returns

A status code indicating success of the function call.

Use this function to switch back to the BLE 2 Mbps PHY from the default 1 Mbps option. You may only call this function after initializing BLE and while the radio is idle.

RAIL_BLE_ConfigPhy2Mbps#

RAIL_Status_t RAIL_BLE_ConfigPhy2Mbps (RAIL_Handle_t railHandle)

Switch to the legacy non-Viterbi 2 Mbps BLE PHY.

Parameters

Type	Direction	Argument Name	Description
RAIL_Handle_t	[in]	railHandle	A handle for RAIL instance.

Returns

A status code indicating success of the function call.

Use this function to switch back to legacy BLE 2Mbps PHY from the default 1 Mbps option. You may only call this function after initializing BLE and while the radio is idle.

DeprecatedNo EFR32 Series 2 parts support BLE non-Viterbi 2 Mbps PHY.

RAIL_BLE_ConfigPhyCoded#

RAIL_Status_t RAIL_BLE_ConfigPhyCoded (RAIL_Handle_t railHandle, RAIL_BLE_Coding_t bleCoding)

Switch to the BLE Coded PHY.

Parameters

Type	Direction	Argument Name	Description
RAIL_Handle_t	[in]	railHandle	A handle for RAIL instance.
RAIL_BLE_Coding_t	[in]	bleCoding	The RAIL_BLE_Coding_t to use

Returns

A status code indicating success of the function call.

Use this function to switch back to BLE Coded PHY from the default 1 Mbps option. You may only call this function after initializing BLE and while the radio is idle. When using a BLE Coded PHY, the RAIL_RxPacketDetails_t::subPhyId marks the coding of the received packet. A subPhyId of 0 marks a 500 kbps packet, and a subPhyId of 1 marks a 125 kbps packet.

RAIL_BLE_ConfigPhySimulscan#

RAIL_Status_t RAIL_BLE_ConfigPhySimulscan (RAIL_Handle_t railHandle)

Switch to the Simulscan PHY.

Parameters

Type	Direction	Argument Name	Description
RAIL_Handle_t	[in]	railHandle	A handle for RAIL instance.

Returns

A status code indicating success of the function call.

Use this function to switch to the BLE Simulscan PHY. You may only call this function after initializing BLE and while the radio is idle. When using Simulscan PHY, the RAIL_RxPacketDetails_t::subPhyId marks the coding of the received packet. A subPhyId of 0 marks a 500 kbps packet, a subPhyId of 1 marks a 125 kbps packet, and a subPhyId of 2 marks a 1 Mbps packet.

Note

: The Simulscan PHY is supported only on some parts. The preprocessor symbol RAIL_BLE_SUPPORTS_SIMULSCAN_PHY and the runtime function RAIL_BLE_SupportsSimulscanPhy() may be used to test for support of the Simulscan PHY.

RAIL_BLE_ConfigChannelRadioParams#

RAIL_Status_t RAIL_BLE_ConfigChannelRadioParams (RAIL_Handle_t railHandle, uint32_t crcInit, uint32_t accessAddress, uint16_t channel, bool disableWhitening)

Change BLE radio parameters.

Parameters

Type	Direction	Argument Name	Description
RAIL_Handle_t	[in]	railHandle	A handle for RAIL instance.
uint32_t	[in]	crcInit	The value to use for CRC initialization.
uint32_t	[in]	accessAddress	The access address to use for the connection. The bits of this parameter are transmitted or received LSB first.
uint16_t	[in]	channel	The logical channel that you're changing to, which initializes the whitener if used.
bool	[in]	disableWhitening	This can turn off the whitening engine and is useful for sending BLE test mode packets that don't have this turned on.

Returns

A status code indicating success of the function call.

This function can be used to switch radio parameters on every connection and/or channel change. It is BLE-aware and will set the access address, preamble, CRC initialization value, and whitening configuration without requiring you to load a new radio configuration. This function should not be called while the radio is active.

RAIL_BLE_PhySwitchToRx#

RAIL_Status_t RAIL_BLE_PhySwitchToRx (RAIL_Handle_t railHandle, RAIL_BLE_Phy_t phy, uint16_t railChannel, uint32_t startRxTime, uint32_t crcInit, uint32_t accessAddress, uint16_t logicalChannel, bool disableWhitening)

Change the current BLE PHY and go into receive.

Parameters

Type	Direction	Argument Name	Description
RAIL_Handle_t	[in]	railHandle	A handle for RAIL instance.
RAIL_BLE_Phy_t	[in]	phy	Indicates which PHY to receive on
uint16_t	[in]	railChannel	Which channel of the given PHY to receive on
uint32_t	[in]	startRxTime	When to enter RX
uint32_t	[in]	crcInit	The value to use for CRC initialization.
uint32_t	[in]	accessAddress	The access address to use for the connection. The bits of this parameter are transmitted or received LSB first.
uint16_t	[in]	logicalChannel	The logical channel that you're changing to, which initializes the whitener if used.
bool	[in]	disableWhitening	This can turn off the whitening engine and is useful for sending BLE test mode packets that don't have this turned on.

Returns

A status code indicating success of the function call.

This function is used to implement auxiliary packet reception, as defined in the BLE specification. The radio will be put into IDLE, the PHY and channel will be changed, and then receive will be entered at the start time given. The new receive will have a timeout of 30 us, which means that this function should only be called if the offset unit is 30 us.

This function is extremely time-sensitive, and may only be called within the interrupt context of a RAIL_EVENT_RX_PACKET_RECEIVED event.

RAIL_BLE_ConfigSignalIdentifier#

RAIL_Status_t RAIL_BLE_ConfigSignalIdentifier (RAIL_Handle_t railHandle, RAIL_BLE_SignalIdentifierMode_t signalIdentifierMode)

Configure and enable signal identifier for BLE signal detection.

Parameters

Type	Direction	Argument Name	Description
RAIL_Handle_t	[in]	railHandle	A RAIL instance handle.
RAIL_BLE_SignalIdentifierMode_t	[in]	signalIdentifierMode	Mode of signal identifier operation.

This features allows detection of BLE signal on air based on the mode. This function must be called once before RAIL_BLE_EnableSignalDetection to configure and enable signal identifier.

To enable event for signal detection RAIL_ConfigEvents() must be called for enabling RAIL_EVENT_SIGNAL_DETECTED.

This function is only supported by chips where RAIL_BLE_SUPPORTS_SIGNAL_IDENTIFIER and RAIL_BLE_SupportsSignalIdentifier() are true.

Returns

Status code indicating success of the function call.

RAIL_BLE_EnableSignalDetection#

RAIL_Status_t RAIL_BLE_EnableSignalDetection (RAIL_Handle_t railHandle, bool enable)

Enable or disable signal identifier interrupt for BLE signal detection.

Parameters

Type	Direction	Argument Name	Description
RAIL_Handle_t	[in]	railHandle	A RAIL instance handle.
bool	[in]	enable	Signal detection is enabled if true, disabled if false.

RAIL_BLE_ConfigSignalIdentifier must be called once before calling this function to configure and enable signal identifier. Once a signal is detected signal detection will be turned off and this function should be called to re-enable the signal detection without needing to call RAIL_BLE_ConfigSignalIdentifier if the signal identifier is already configured and enabled.

This function is only supported by chips where RAIL_BLE_SUPPORTS_SIGNAL_IDENTIFIER and RAIL_BLE_SupportsSignalIdentifier() are true.

Returns

Status code indicating success of the function call.