All the notable changes to this project are documented in this file.
All the notable changes included in the nRF Connect SDK v2.1.2 release are documented in this section.
On nRF53, the fix for Errata 158 is now applied.
All the notable changes included in the nRF Connect SDK v2.1.0 release are documented in this section.
Support for changing the radio transmitter’s default power level using
Support for disabling or enabling peripheral latency using
Stub version of
sdc_hci_get()for getting all types of HCI packets from the Link Layer (DRGN-17060).
Experimental support for generic coex (DRGN-17128).
When the SoftDevice Controller is used with the Front-End Module provided by the Multiprotocol Service Layer, the transmit power is expressed as the power on the antenna instead of the power of the SoC output. This allows dynamic gain control of the Front-End Module if the selected Front-End Module supports it. The default transmit power for Bluetooth LE activities does not change, so if the Front-End Module has an exemplary gain of +10 dB, the output power of the SoC will be decreased accordingly. To achieve higher output powers on the antenna, the user must call the appropriate API. For
sdc_hci_cmd_vs_zephyr_write_tx_power()the transmit power is expressed as the maximum power on the antenna. The returned transmit power is the power on the antenna that can be achieved on the current SoC and Front-End Module. For
sdc_hci_cmd_vs_zephyr_read_tx_power()the returned transmit power is the power on the antenna that can be achieved on the current SoC and Front-End Module. (KRKNWK-13714)
Improved channel selection for secondary advertising packets (DRGN-17452).
The extended advertiser will now always include the SyncInfo in the AUX_ADV_IND if there is a corresponding periodic advertiser, even if the offset cannot be represented (DRGN-16240).
sdc_support_phy_update_peripheral(), to enable change of PHY independently of the functions
sdc_support_le_2m_phy()These changes reduce the code size when using only central or peripheral role. (DRGN-17592)
Applications may now configure fewer TX/RX buffers than the default. Note that this may lead to reduced throughput (DRGN-17651).
The scanner is now scheduling cooperatively when the sum of scan windows is equal to the scan interval. This improves scheduling performance when scanning concurrently on multiple PHYs (DRGN-17754).
Improved scheduling performance when synchronized to a periodic advertiser sending packets on Coded PHY (DRGN-17754).
Fixed a HardFault that could occur when receiving legacy PDUs while using the periodic advertising synchronization functionality (DRGN-17656).
Fixed an issue where the maximum data length capabilities were set to 27 bytes when the configured event length (
CONFIG_BT_CTLR_SDC_MAX_CONN_EVENT_LEN_DEFAULT) was more than 65535 us (DRGN-17454).
Fixed an issue where using the memory macros in
sdc.hwith fewer TX/RX buffers than the default would report incorrect memory usage (DRGN-17651).
Fixed an issue where the periodic advertiser sends its AUX_SYNC_IND 40 us later than indicated in the SyncInfo of the AUX_ADV_IND packet (DRGN-17710).
Fixed an issue where the scanner would attempt to receive the first AUX_SYNC_IND 40 us later than indicated in the SyncInfo of the AUX_ADV_IND packet (DRGN-17710).
All the notable changes included in the nRF Connect SDK v2.0.0 release are documented in this section.
Support for Peripheral-initiated Feature Exchange.
Support for periodic advertising intervals larger than ten seconds (DRGN-16873).
Support for periodic sync timeouts larger than 128 seconds (DRGN-16434).
sdc_support_ext_central()function that makes the extended initiator role configurable (DRGN-16392).
Support for connectionless angle of arrival (AoA) transmitter (DRGN-16588). The following HCI commands are now supported (DRGN-16713):
LE Set Connectionless CTE Transmit Parameters
LE Set Connectionless CTE Transmit Enable
LE Read Antenna Information
Support for Periodic Advertising ADI (DRGN-16759).
nak_countfield into QoS Connection event reports that counts the number of received Negative Acknowledges from the peer during the connection event. See
sdc_coex_adv_mode_configureAPI to configure the behavior of the advertiser when using the coexistence interface (DRGN-16585).
Update public API terms to Bluetooth Core Specification v5.3 (DRGN-16271)
SDC_DEFAULT_MASTER_COUNThas been renamed to
SDC_DEFAULT_SLAVE_COUNThas been renamed to
SDC_MEM_PER_MASTER_LINKhas been renamed to
SDC_MEM_PER_SLAVE_LINKhas been renamed to
SDC_MEM_MASTER_LINKS_SHAREDhas been renamed to
SDC_MEM_SLAVE_LINKS_SHAREDhas been renamed to
SDC_CFG_TYPE_MASTER_COUNThas been renamed to
SDC_CFG_TYPE_SLAVE_COUNThas been renamed to
sdc_cfg_t.master_counthas been renamed to
sdc_cfg_t.slave_counthas been renamed to
sdc_support_master()has been renamed to
sdc_support_slave()has been renamed to
HCI interface was updated according to Bluetooth Core Specification v5.3. For a list of the original terms and names and their replacements, refer to Appropriate Language Mapping Table.
The scanner now waits until the host has pulled the previous event’s periodic advertising reports before enqueuing a report for the next event. Note that this does not apply to single-PDU periodic advertising events (DRGN-16920).
The binary size of an application using the scanner but not the central role is decreased (DRGN-16392).
Removed support for running the SoftDevice Controller on the nRF5340 PDK (DRGN-15174).
VersNrfield in the
LL_VERSION_INDpacket now contains the value 0x0C to indicate compatibility with Bluetooth Core Specification v5.3 (DRGN-16109).
sdc_hci_subevent_vs_qos_conn_event_report_tstructure has been redefined (DRGN-17183).
Fixed an issue where Advertiser Address Type in the LE Periodic Advertising Sync Established event was never set to 0x02 or 0x03, even if the advertiser’s address was resolved (DRGN-17110).
Fixed an issue where Advertiser Address Type was not set in the LE Periodic Advertising Sync Established event when using the Periodic Advertiser List (DRGN-17110).
Fixed an issue where setting advertiser radio output power using the vendor-specific HCI command Zephyr Write TX Power Level returned “Unknown Advertiser Identifier (0x42)”.
Fixed an issue where reading advertiser radio output power using the vendor-specific HCI command Zephyr Read TX Power Level returned “Unknown Advertiser Identifier (0x42)”.
Fixed an issue where an assert could occur if
sdc_disable()was called while a Bluetooth role was running (DRGN-16515).
Fixed an issue where the advertiser would incorrectly set Offset Adjust in the SyncInfo when the offset to the
AUX_SYNC_INDis large (DRGN-16887).
Fixed an issue where issuing a legitimate connection update could result in an
Fixed an issue where connecting to the same device using a different address got denied as a duplicate connection (DRGN-17232).
All the notable changes included in the nRF Connect SDK v1.9.0 release are documented in this section.
Added support for Periodic Advertising for production for nRF52 Series.
Added support for a vendor-specific HCI command setting the periodic advertising event length (DRGN-16513).
SDC_CFG_TYPE_PERIODIC_ADV_LIST_SIZEto allow the application to configure the size of the periodic advertiser list (DRGN-16357).
Fixed an issue on the nRF53 Series where an assert could occur when connected as a peripheral, and the RC oscillator is used as the Low Frequency Clock source (DRGN-16808).
All the notable changes included in the nRF Connect SDK v1.8.0 release are documented in this section.
SDC_CFG_TYPE_PERIODIC_ADV_COUNTcan be used to set the number of periodic advertisers.
SDC_CFG_TYPE_PERIODIC_SYNC_COUNTcan be used to set the number of synchronizations to periodic advertisers.
SDC_CFG_TYPE_PERIODIC_SYNC_BUFFER_CFGcan be used to configure the number of periodic synchronization report buffers.
The following HCI commands are now supported (DRGN-11505):
LE Set Periodic Advertising Data
LE Set Periodic Advertising Enable
LE Set Periodic Advertising Parameters
LE Periodic Advertising Create Sync
LE Periodic Advertising Create Sync Cancel
LE Periodic Advertising Terminate Sync
LE Add Device To Periodic Advertiser List
LE Remove Device From Periodic Advertiser List
LE Clear Periodic Advertiser List
LE Read Periodic Advertiser List Size
LE Set Periodic Advertising Receive Enable
The default advertising data size is now 31 bytes, even for extended advertising (DRGN-16209).
SDC_CFG_TYPE_ADV_BUFFER_CFGcan be used to change the maximum buffer size before enabling the controller. The required memory for an advertising set with a given advertising data size will then be returned by
sdc_cfg_scan_buffer_cfg_tis replaced with
The controller will now prevent establishing a connection to a device it is already connected to (DRGN-15989).
Fixed an issue where the active scanner could assert when performing extended scanning on Coded PHY with a full whitelist (DRGN-16113 and DRGN-16013).
Fixed an issue where extended advertising reports with advertising data with length 228 were lost (DRGN-16341).
Fixed an issue where the peripheral would always listen on data channel 0 if the initiator sent a connection request with all channels marked as bad (DRGN-16394).
Fixed an issue where an assert may occur when switching from a faster to a slower PHY (DRGN-15547). The assert would only occur when:
Fixed an issue where the host callback was called after an advertising event even if there were no events generated (DRGN-16405).
Fixed an issue where a MPU fault may occur when switching between extended and legacy advertising (NCSIDB-572).
All the notable changes included in the nRF Connect SDK v1.7.0 release are documented in this section.
SDC_CFG_TYPE_SCAN_BUFFER_CFGto allow the application to configure the number of scan buffers (DRGN-15899).
SDC_CFG_TYPE_ADV_BUFFER_CFGto allow the application to configure the maximum advertising buffer size (DRGN-15661).
Direct_Addressin extended advertising reports are updated to reflect the latest BLE specification. See Specification errata 14566 and 15752 (DRGN-15927).
The scanner is now scheduling cooperatively when the scan window is equal to the scan interval. This improves the performance in the case of Bluetooth Mesh applications (DRGN-13146).
Support for radio front-end module (FEM) in nRF53 Series, based on the Front-end module feature (DRGN-14908).
The application must now call the APIs prefixed with
Fixed an issue where the scanner did not check that the scan window was smaller than the scan interval (DRGN-15586).
Fixed an issue where the channel map provided by the “LE Host Set Channel Classification” HCI command was not always applied on the secondary advertising channels (DRGN-15695).
Fixed an issue on the nRF53 Series where an assert could occur while scanning using legacy commands (DRGN-15852).
Fixed an issue on the nRF53 Series where the scanner could generate corrupted advertising reports (DRGN-15852).
Fixed an issue where the
mpsl_tx_power_channel_map_set()API would not work on peripheral-only or central-only configurations (DRGN-16091).
Fixed an issue where an assert may occur when legacy advertiser is used after “HCI LE Clear Advertising Sets” (DRGN-15993).
Fixed an issue where an assert could occur when in LLPM mode and the connection interval was more than 1 ms (DRGN-16079).
All the notable changes included in the nRF Connect SDK v1.6.0 release are documented in this section.
Added support for multiple advertising sets (DRGN-15426).
Added radio front-end module (FEM) support, based on the Front-end module feature (nRF52 Series only) (DRGN-11059).
Added support for the vendor-specific HCI command: Read Supported Vendor Specific Commands (DRGN-13763).
Added support for the vendor-specific HCI command: Zephyr Read Key Hierarchy Roots (DRGN-13237).
Added support for nRF5340, which was previously only supported for evaluation purposes (DRGN-8639).
Increased the maximum supported radio output power on nRF53 Series devices from 0 dBm to 3 dBm. If the output power is above 0 dBm, NRF_VREQCTRL->VREGRADIO.VREQH is set (DRGN-15476).
SDC_DEFAULT_RX_PACKET_COUNTfrom 3 to 2. Now the controller can achieve full throughput with only two RX buffers (DRGN-7696).
Decoupled the controller from the random number generator (DRGN-12507). This functionality must now be provided by the user. The user must provide
rand_poll()through the newly introduced
sdc_rand_source_register(). These functions can be mapped to the Zephyr Entropy APIs:
*_isr()for nonblocking behavior)
Fixed an issue where a slave connection could disconnect prematurely if there were scheduling conflicts with other roles (DRGN-15469).
Fixed an issue where the channel map provided by the LE Host Set Channel Classification HCI command was not applied on the secondary advertising channels (DRGN-13594).
The SoftDevice Controller can now be qualified on nRF52832 (DRGN-15382).
Fixed an issue where setting a legacy advertiser’s scan response data using extended advertising HCI commands corrupted the advertising data (DRGN-15465).
Fixed an issue where, in rare cases, an assert could occur when receiving a packet as a slave. This could only occur after performing a data length procedure on Coded PHY (DRGN-15251).
Fixed an issue where “HCI Read RSSI” would always return a Command Disallowed (0x0C) error code (DRGN-15310).
Fixed an issue where setting radio output power using the vendor-specific HCI command Zephyr Write TX Power Level returned “Unsupported Feature or Parameter value (0x11)”. Now the controller will select an output power level that is lower or equal to the one requested. The command returns success and the selected power level (DRGN-15369).
Fixed an issue where an assert could occur when running an extended advertiser with maximum data length and minimum interval on Coded PHY. The assert would only occur if there were scheduling conflicts (DRGN-15694).
Fixed an issue where a connectable or scannable advertiser ends with sending a packet without listening for the CONNECT_IND, AUX_CONNECT_REQ, and SCAN_REQ (DRGN-15484).
Fixed an issue where an extended advertiser with limited duration may time out after the first primary channel packet in the last advertising event (DRGN-10367).
Fixed an issue where the coding scheme provided by the LE Set PHY HCI Command was ignored after a remote initiated PHY procedure (DRGN-15531).
Fixed an issue where the controller may still have pending events after
sdc_hci_evt_get()returns false. This would only occur if the host has masked out events (DRGN-15758).
Fixed an issue where the extended scanner generated reports containing truncated data from a chained advertising PDU (DRGN-13338).
All the notable changes included in the nRF Connect SDK v1.5.0 release are documented in this section.
sdc_support_ext_scan()which makes support for extended scanning configurable (DRGN-14902).
sdc_support_ext_adv()which makes support for extended advertising configurable (DRGN-14914).
Added support for the vendor-specific HCI command: Zephyr Read Chip Temperature (DRGN-13769).
Added support for the vendor-specific HCI command: Zephyr Read Tx Power (DRGN-15250).
Renamed and reconfigured the libraries (DRGN-15118). Refer to the README for their corresponding supported feature sets. The new names are now:
All libraries are now compatible with all platforms within a given family (DRGN-15118).
Fixed an issue where the application could not immediately restart a connectable advertiser after a high duty cycle advertiser timed out (DRGN-13029).
Fixed an issue where a directed advertiser used a resolvable address as the
TargetAwhen the local device address was set to public or random device address (DRGN-13921).
Fixed an issue where “HCI LE Set Extended Advertising Parameters” should have returned “Packet Too Long (0x45)” when the advertising set was already configured with data that was longer than it could fit within the advertising interval. Previously, the advertising data was cleared every time the advertising set was configured (DRGN-14008).
Fixed an issue where the link would disconnect with reason “LMP Response Timeout (0x22)”. This would occur if the “HCI LE Long Term Key Request event” was disabled and the slave received an encryption request (DRGN-15226).
Fixed an issue where the LL control procedures LE start encryption and LE connection parameter update could not be initiated at the same time (DRGN-11963).
Fixed an issue where the generation of QoS Connection event was not disabled after an HCI reset (DRGN-15291).
See the Known issues page in nRF Connect SDK for the list of known issues and limitations for this release.
All the notable changes included in the nRF Connect SDK v1.4.0 release are documented in this section.
Added Read Transmit Power Level command (DRGN-12236).
Added LE Read Transmit Power command (DRGN-12236).
Added LE Read Advertising Physical Channel Tx Power command (DRGN-12238).
Added support for setting the event length of a connection. See
Added Set Controller to Host Flow Control command (DRGN-13331).
Added Host Buffer Size command (DRGN-13331).
Added Host Number of Complete Packets command (DRGN-13331).
Added support for the vendor-specific HCI command: Zephyr Write BD Addr (DRGN-14511).
Added LE Read PHY command (DRGN-14664).
Added APIs for every supported HCI command (DRGN-13723).
sdc_support_adv()which makes the advertising state configurable (DRGN-14759).
sdc_support_slave()which makes the slave role configurable (DRGN-14759).
sdc_support_scan()which makes the scanning state configurable (DRGN-14759).
sdc_support_master()which makes the master role configurable (DRGN-14759).
When linking the final binary, the image size is reduced. Only the requested features are included. See
sdc_support_adv()and similar APIs for more details.
When LLPM mode is enabled, the connection event length is now no longer implicitly set to 1 ms (DRGN-12696).
When the connection interval is an LLPM connection interval, that is, below 7.5 ms, link-layer procedures with an instant will use an instant larger than 6 connection events (DRGN-14379).
The nRF Bluetooth LE Controller was renamed to SoftDevice Controller (DRGN-14283). APIs are updated accordingly:
BLE_CONTROLLER -> SDC
ble_controller -> sdc
HCI APIs are now prefixed with sdc
The name of the library file was changed to
SoC APIs have been renamed (DRGN-14283):
ble_controller_flash_write -> sdc_soc_flash_write_async
ble_controller_flash_page_erase -> sdc_soc_flash_page_erase_async
ble_controller_rand_vector_get -> sdc_soc_rand_vector_poll
ble_controller_rand_vector_get_blocking -> sdc_soc_rand_vector_get
ble_controller_ecb_block_encrypt -> sdc_soc_ecb_block_encrypt
Vendor-specific HCI APIs have been renamed (DRGN-14701):
HCI_VS_OPCODE -> HCI_OPCODE_VS
HCI_VS_SUBEVENT -> HCI_SUBEVENT_VS
hci_vs_cmd -> hci_cmd_vs
Fixed an issue in the master role which could cause disconnects if there were scheduling conflicts while doing control procedures with an instant (DRGN-11222).
See the Known issues page in nRF Connect SDK for the list of known issues and limitations for this release.
All the notable changes included in the nRF Connect SDK v1.3.0 release are documented in this section.
Added Read Authenticated Payload Timeout command.
Added Write Authenticated Payload Timeout command.
Added Set Event Mask command.
Added Set Event Mask Page 2 command.
ble_controller_support_le_2m_phy()which makes LE 2M PHY support configurable.
ble_controller_support_le_coded_phy()which makes LE Coded PHY support configurable.
Added LE Read Supported States command.
Added LE Set Advertising Set Random Address command.
Added LE Remove Advertising Set command.
Added LE Clear Advertising Sets command.
Added support for the vendor-specific HCI command: Zephyr Read Version Information.
Added support for the vendor-specific HCI command: Zephyr Read Supported Commands.
Added support for the vendor-specific HCI command: Zephyr Read Static Addresses.
Added support for the vendor-specific HCI command: Zephyr Write TX Power Level (per Role/Connection).
HCI_VS_SUBEVENT_CODE_QOS_CONN_EVENT_REPORTwas renamed to
hci_vs_evt_qos_conn_event_report_twas renamed to
hci_vs_cmd_zephyr_read_supported_commands_return_twas converted from a struct to a union. The content remains the same.
The VersNr field in the LL_VERSION_IND packet now contains the value 0x0B to indicate Bluetooth Core Specification v5.2 compliance.
The previously implemented Vendor Specific HCI command opcodes are now offset with 0x100.
The previously implemented Vendor Specific HCI event codes are now offset with 0x80.
When the controller receives an unknown command, it will raise “Command Status event” instead of “Command Complete event”.
When in slave latency, the controller now picks up data from the host for transmission earlier than it used to.
In the LE Extended Advertising Report, the Direct Address Type values 0x02, 0x03, and 0xFE will only be used when the Scanning Filter Policy is equal to 0x02 or 0x03 and TargetA is a resolvable private address. If the address is resolved, then the Direct Address Type will contain the same value as the Own Address Type parameter of the command LE Set Extended Scan Parameters. This follows the Bluetooth Core Specification v5.2.
On nRF53, the fix for Errata 16 is now applied.
All the notable changes included in the nRF Connect SDK v1.2.0 release are documented in this section.
ble_controller_support_dle()which makes LE Data Length Extension support configurable.
Added preliminary support for the S140 variant with the nRF5340 device. The Bluetooth LE Controller for nRF5340 supports the same feature set as its nRF52 Series counterpart. The following library has been added:
Clock accuracy must now be specified in parts per million (ppm) instead of the previous enum value.
The IRQ line to pend for low priority signal processing must be provided to
The application must call
ble_controller_low_prio_tasks_process()to process low priority signals.
Interrupt handler APIs for the following peripherals are moved to MPSL: RADIO, RTC0, TIMER0, and POWER_CLOCK.
High-frequency clock API (
ble_controller_hf_clock_...) is removed. Use the corresponding API in MPSL instead.
Temperature API (
ble_controller_temp_get()) is removed. Use the corresponding API in MPSL instead.
Timeslot API is removed. Use the corresponding API in MPSL instead.
Version numbers have been removed from the libraries.
Fixed an issue where the application could not immediately restart a connectable advertiser after a high duty cycle advertiser timed out.
Fixed an issue where a control packet could be sent twice even after the packet was ACKed. This would only occur if the radio was forced off due to an unforeseen condition.
Fixed an issue in HCI LE Set Extended Scan Enable where
UNSUPPORTED_FEATUREwas returned when duplicate filtering was enabled.
Fixed an issue in HCI LE Set Advertising Parameters where
UNSUPPORTED_FEATUREwas returned when
secondary_max_skipwas set to a non-zero value. This issue occurred when sending a packet on either LE 1M or LE 2M PHY after receiving or transmitting a packet on LE Coded PHY. If this occurred while performing a Link Layer Control Procedure, the controller could end up retransmitting an ACKed packet, resulting in a disconnect.
Fixed an issue where an assert could occur when receiving a packet with a CRC error after performing a data length procedure on Coded PHY.
Fixed an issue where an assert occurred when setting a secondary PHY to 0 when using HCI LE Set Extended Advertising Parameters. This issue occurred when the advertising type was set to legacy advertising.
All the notable changes included in this release are documented in this section.
Added support for nRF52833.
Fixed an issue where
hci_data_get()could return “No data available” when there was data available. This issue would only occur when connected to multiple devices at the same time.
All the notable changes included in this release are documented in this section.
Fixed an issue where an assert occurred when the host issued LE Write Suggested Default Data Length.
All the notable changes included in this release are documented in this section.
Increased the number of supported SoC and library combinations.
Added API for estimating the dynamic memory usage returned by
Added a new header
ble_controller_hci_vs.hthat exposes definitions of Vendor-Specific HCI commands and events.
Added support for connection intervals less than the standard minimum of 7.5 ms. Note that this is a proprietary feature that is not Bluetooth compliant. This proprietary feature is named ‘Low Latency Packet Mode (LLPM)’.
Added support for enabling or disabling connection event length extension. When disabled, the maximum connection event length is set by
ble_controller_cfg_event_length_t::event_length_us. When enabled, the maximum connection event length is determined by the connection interval.
Added support for generating QoS Connection event reports. When enabled, one report is generated with every connection event. The report contains information that can be used to change the Bluetooth LE channel map.
Fixed an issue where the “HCI Read Local Supported Commands” command did not indicate support for the “HCI LE Set Privacy Mode” command.
Fixed an issue where an ASSERT occurred when setting advertising data after HCI Reset without setting advertising parameters.
Fixed an issue where an ASSERT occurred when writing to flash.
Fixed an issue where a directed advertiser could time out without sending a packet on air.
VersNrfield in the LL_VERSION_IND packet now contains the value 0x0A to indicate Bluetooth Core Specification v5.1 compatibility.
Bluetooth Core Specification Erratum #10750 is incorporated. The LE Data Length Change event will now be raised when switching to and from Coded PHY. On-air behavior has not changed.
Bluetooth Core Specification Erratum #10818 is incorporated. The controller now allows HCI ACL data packets with a 0-length payload but does not transmit anything until receiving the next non-zero continuation fragment.
Cleaned up invalid Doxygen comments.
Added a workaround to block the host from sending HCI commands when a shared command is in progress.
Fixed a bug causing an assert in
Minor documentation fixes.
Added names to nested structs and unions in
timeslot.has a workaround for a Sphinx documentation build issue.
Fixed internal links to functions and files.
Updated Bluetooth LE Controller with bug fixes and updated APIs.
Added API for fetching build revision information.
ble_controller_rand_vector_get_blocking()as a blocking call to get a vector of random bytes.
Added API to get Bluetooth LE Controller build revision:
Fixed an issue in HCI control flow that severely limited Bluetooth LE throughput.
ble_controller_process_SWI5_IRQ()to be IRQ independent. The generic
ble_controller_low_prio_tasks_process()is used instead and SWI5 is no longer reserved.
Aligned naming for Bluetooth LE Controller configuration names.
Made minor changes to existing API.
Improved API documentation.
No change to library files.
Added the headers necessary to utilize the timeslot API.
Added the following ble_controller_nrf52_0.1.0-1.prealpha library variants, each in soft-float, softfp-float, and hard-float builds: