MeshConnect 2011

The MT MeshConnect 2011 is a gateway for the Meshtech network and supports a set of backend protocols.

6.3.2 - 2024-03-19

Changed

• Make sure throughput test packets sent downstream are padded to 20 bytes
• Firmware caching improvements
• Updated to .NET 7.0.17

Fixed

• BLE FW: Full scan was not started when scan-mode set to 'Scan' (0) while automatically scanning for reconnects.

6.3.1 - 2024-02-08

Fixed

• Firmware upgrade of newer devices sometimes failed.

6.3.0 - 2024-02-02

In this release we have added support for Network Mode. The PowerSaving mode can be used in networks with extenders that support the internal property 0xFF00 - Scan Mode.

This release also introduces internal properties. These are not reported by the gateway, but are readable.

• Network Protocol: 1.10
• Identifier Dictionary: 9

Added

• New properties:
  • 0x8228 - Network Mode
  • 0xFF00 - Scan Mode
• Identifier Dictionary update (version 9):
  • 0x8228 - network-mode
  • 0xFF00 - scan-mode
  • 0x8850 - enocean-config
  • 0x8858 - enocean-ptm-215b-data
• Network Protocol 1.10
  • New flag to include/exclude root extender (GW) in multicast.
  • Internal properties. Properties with identifiers starting with 0xFF are treated as network internal.
• Multicast of firmware model numbers 0x0040 and 0x0043 are now limited to extenders

Changed

• Updated to .NET 7.0.15
• Updated BLE GW firmware
  • Not always able to establish connection to unconnected devices.

6.2.0 - 2023-12-13

In this release we have made improvements to the network protocol to speed up connection establishment. The network formation time is also reduced. To get the maximum benefit from this improvement, all devices should be upgrade to a version that implements network protocol version 1.9 or later.

This version is also needed to support upgrading firmware based on nRF Connect SDK (NCS).

• Network Protocol: 1.9
• Identifier Dictionary: 8

Added

• New properties:
• 0x8322 network-tree
• Support for firmware updates based on nRF Connect SDK (NCS)

Changed

• MT2 version 2.0.1 patch release (minor fixes)
• Updated to .NET 7.0.14
• Updated BLE GW firmware

6.1.0 - 2023-06-02

In this release we have added support for firmware broadcast. This new way of updating firmware for connected devices is much more efficient and takes less time than regular firmware download.

The release also contains a few other new features and improvements.

• Network Protocol: 1.8
• Identifier Dictionary: 7

Added

• New properties:
  • 0x8124 start-firmware-broadcast
  • 0x8125 firmware-broadcast-state
  • 0x8126 firmware-broadcast-control
  • 0x8251 log-debug
  • 0x8252 log-rx
  • 0x8253 log-tx
• New statistics counters:
  • NodeRemoved
  • ExtenderRemoved
  • OutOfSyncFirmwareBlockRequest
• Support for broadcasting downstream throughput test
• Report systemProductId, systemSerialId, systemName and appId to Management

Changed

• Debug (DBG) level entries are not written to log by default. Property 'log-debug' must be set to true to enable this.
• Getting network tree / devices from Management is now faster (due to compression)
• Getting log from Management is now faster (due to compression)

6.0.0 - 2023-02-10

In this version we've done changes to the connection intervals to balance and improve the transfer capacity in the network. We've also done changes to the network tree formation to optimize the tree structure.

• Network Protocol: 1.7
• Identifier Dictionary: 6

Added

• Support for extended route addresses
• Support for new node/temporary device types supporting extended route address.
• Newer device firmware versions will require this support in order to establish connection.
• Property '83.08 - Try LTE' (command)
• Reporting of network interface type to Device Management (LTE/Ethernet)
• Support for storage mode reporting with variant.
• Newer device firmware require this support to be detected in storage mode.
• 'storage-mode-event' will include variant in this case.
• JSON translations for identifier dictionary version 6.

Changed

• Connection interval increased from 90 to 188.75 ms.
• Scan interval increased from 22.5 ms to 188.75 ms (scan-window <= 45%).
• Scan interval will be 22.5 ms when scan-window > 45%.
• Network tree formation algorithm will try to build a wider tree structure.
• Supervision timout for node connections increased from 8 to 24 seconds.
• Extender and Temporary connections have 8 seconds timeout.
• Updated to .NET 7.0.2

Fixed

• Downloading gateway firmware sometimes time out when using a slow LTE connection.
• Default timeout increased from 10 mintues to 30 minutes (timeout = 0 in start-firmware-update)
• When timeout is not 0 in start-firmware-update, that timeout is used.

5.1.0 - 2022-11-28

• Network Protocol: 1.5
• Identifier Dictionary: 5

Added

• Add Ethernet/LTE switching feature. LTE variants will try to use Ethernet first. If unable to connect to Management for 3 minutes, switch network interface and reboot. When on LTE, write to '83.08 - Try Ethernet' to manually switch back to Ethernet.
• Add properties related to Ethernet/LTE switching:
  • 83.08 - Try Ethernet (command)
  • 91.08 - Network Interface
• Add 'Throughput Test' feature. New properties:
  • 83.04 - Start Downstream Throughput Test (command)
  • 83.05 - Throughput Test Packet Counter
• Add JSON translations for identifier dictionary version 5

Changed

• Update to .NET 7

Fixed

• Reduce chance of overflow (128 KB limit) when requesting network tree/devices from Management.

5.0.0 - 2022-11-01

Added

• Implement improvements in network protocol version 1.5
  • Improved network formation algorithm
• New property "90.20 - Offer RSSI Threshold"
  • IMPORTANT: The default value of this property is -90 dBm. The gateway will now require an RSSI level above this threshold to offer connectivity. Connected devices (extenders and nodes) with RSSI below this level (weak links) might not be able to establish connection. To allow such weak connections, write a lower value to this property.
• New read-only property "84.11 - Upstream packet lost"
• Add JSON translations for identifier dictionary version 4
• Support for identifier value extensions

Changed

• Remove reporting of "81.01 - Uptime"
• Keep cached property values when flushing
• MT2 API updated to version 2.0.0.
  • BREAKING topic changes ('decoded' and 'raw' mode)
  • Added read/write response metadata
  • Added ext field
• Update to .NET 6.0.10
• Allow both LTE and 3G networks

Fixed

• Allow writing NULL to "91.30 - Ethernet IP Configuration" to go back to using DHCP

Components

Component	Version
Network Protocol	1.5
Identifier Dictionary	4
MT2 API	2.0.0
MBE API	3.3.0

4.7.0 - 2022-06-29

• Network Protocol: 1.4
• Identifier Dictionary: 3

Added

• Implement new improvements in network protocol version 1.3/1.4
• Count number of heartbeat messages/duplicates received by the gateway
• Added 'lastCount' in heartbeat payload for MT2, GCP and EclipseHono.
• MT2 API version increased to 1.3.0
• Reduce Management connection watchdog timeout from 24h to 1h
• Reset LTE modem

Changed

• Update .NET 6 Runtime to version 6.0.6
• BLE GW firmware updated
• Require LTE cellular network mode (MeshConnect 2011)

Fixed

• Improved performance of network tree formation in BLE GW firmware. Sometimes formation could take very long time.
• Detecting rare situation where BLE firmware stack fails to establish connections. The BLE GW will do a soft reset to break out of this error state.
• Reset LTE modem at startup. This will resolve potential locked modem state. (MeshConnect 2011)
• Catch exceptions when decoding property values when getting network tree/devices from Management. If there is an issue with one property value, it should skip only that property instead of failing the entire request.

4.6.0 - 2022-02-10

Added

• Add statistics (Meshtech Management)
• Add errorcode reporting (Meshtech Management)
• Add read/write property metadata (Meshtech Management)
• ResponseTime, Origin, Relay Device/Route.
• Trigger a reboot if Management connection has been down continuously for 24 hours (MeshConnect 2011)
• Add keep-alive ping for BLE GW device/dongle

Changed

• Allow multiple outstanding device requests
• Update .NET 6 Runtime to version 6.0.2
• Shorten LTE connection polling interval from 5 minutes to ~1 minute (MeshConnect 2011)

Fixed

• Try to bring up LTE connection before making connections (MeshConnect 2011)

4.5.0 - 2021-12-15

• Network Protocol: 1.2
• Identifier Dictionary: 3

Added

• New backend config: GCP (Google Cloud IoT Core). API version: 1.0.0-beta.1.
• Hold up to ~1.3 MB of the latest log entries in memory.
• New property: '82.50 - Log To Disk'. When set, up to ~2.6 MB of latest log entries are written to disk.
• New property: '91.11 - ICCID' (MT MeshConnect 2011 with LTE)
• Extend MT2 backend config with two new optional properties: topicPrefix and disableSubscribe. Version of MT2 increased to 1.2.0.
• Add new identifier translations (dictionary version 3)
• New property: '82.30 - General Advertisement Reporting'.
• Network Protocol 1.2 features:
• Generate RSSI updates from Non-Meshtech devices when enabled using property 82.30.
• Generate RSSI updates and report new property '81.60 - Ping Counter' for devices that are pinging.
• Generate '98.09 - Alarm 2' property update from devices that support this.
• New management features (API version 2)
• Report ICCID (SIM card identifier) to Management (MT MeshConnect 2011 with LTE)
• Support for read-raw and write-raw from Management
• Fetch log (debug feature)
• Support for getting unconnected devices
• Getting 'last seen' for each device
• Support for deleting backend config (using job)
• New property: 81.60 - Ping Counter (MT MeshConnect 2021). This enable the gateway itself to ping.
• Generate a heartbeat when backend connected.

Changed

• Update to .NET 6

4.4.0 - 2021-10-05

Added

• Official support for Cisco IOx platform (MT MeshConnect 2021)

Changed

• Improve routing algorithm for Unconnected devices
• Update .NET 5 Runtime to version 5.0.10

Fixed

• Remove >-86 dBm hard-limit for considering RSSI samples for routing. This limit caused Unconnected devices with weak signal to be unreachable.

4.3.0 - 2021-08-26

Changed

• Version of Diagnostics API set to 1.0.0 (previously 1.0.0-beta.9)
• Removed MT message packet buffer size restriction
• Logging performance improvements
• Added date to log line entry
• Firmware download timeout increased from 2 minutes to 10 minutes
• Update .NET 5 Runtime to version 5.0.9

Fixed

• Automatic firmware download from Management not always started
• Deadlock when setting WireGuard configuration from Management
• Massive reporting of firmware-update-state property during gateway firmware update

4.2.0 - 2021-07-01

• Network Protocol: 1.1
• Identifier Dictionary: 2

Added

• Support for requesting network tree from Device Management
• Support for read/write property from Device Management
• Support for setting WireGuard configuration from Device Management

Changed

• Devices in DFU mode will use sequence number -1 for rssi signal updates. In previous versions, no sequence number was provided.
• New and improved provisioning to Device Management
• Increase device request timeout from 30 to 45 seconds
• Update .NET 5 runtime to 5.0.7

Fixed

• Improve routing to Unconnected devices by making it adapt faster to changes in signal.
• Formatting of hardware version when reporting to Device Management

4.1.0 - 2021-05-11

• Network Protocol: 1.1
• Identifier Dictionary: 2

Added

• Added property 81.32 - Nordic DFU Control

Changed

• MBE API rolled back to version 3.3.0
• Updated Identifier Dictionary
• BLE GW firmware updated to version: 56.1.0

4.0.0 - 2021-04-27

In this release we have done some improvements to the Meshtech Network Protocol to improve reliability. To use device firmware that implement version 1.1 of the protocol, the gateway must also be updated. Version 1.1 is fully backwards compatible with the initial version (1.0), so one can update the gateway without updating device firmware.

This version also implements translation of raw hex identifiers to string/JSON. The translation dictionary is version 1. As we add support for translation of new identifiers, we will document this and increase the version number.

• Meshtech Network Protocol Version: 1.1
• Meshtech Identifier Dictionary Version: 1

Added

• Added property 82.22 - Measurement Reporting (default: true)
• Added property 82.23 - Event Reporting (default: true)
• Added property 91.30 - Ethernet IP Configuration (default: null)
• MT2 API now supports 'decoded' mode
• Eclipse Hono backend API 1.0.0-beta.2 (BETA)

Changed

• Implemented improvements in Meshtech Network Protocol 1.1
• MBE API updated to version 4.0.0
• Changed subscribe topic filter for MT2 API. Version changed to 1.1.1.
• Updated from .NET Core 3.1 to .NET 5
• Performance improvements and better CPU utilization
• Improved status monitoring of data sent to backend API. Automatic disconnect on send-failure.
• BLE GW firmware updated to version: 56.0.0
• Update .NET 5 runtime to 5.0.5

Fixed

• Crash when using LTE and reporting 91.10 - Cellular Network Information
• Slow detection of MT2 API disconnected state
• Various minor fixes and improvements

Removed

• MT API (predecessor to MT2)

3.5.0 - 2021-02-03

Added

• Watchdog for main-loop (2 minutes timeout)
• Main-loop iteration time monitoring and performance reporting to log every 60 minutes
• Support for NULL property value reporting packet (49)
• New property: 91.10 - Cellular Network Information (4G versions only)
• New property: 91.20 - Geographic Point Location (GPS versions only)

Changed

• Priority of firmware data packets (downstream) increased from Lowest to Low
• Do not update 91.10 - Rssi with Parent implicitly on status updates
• Improved BLE GW firmware update
• Improved device disconnect handling
• Clear and rebuild network after BLE GW reset
• Increase priority for edge discovery request at startup to High
• Increase priority of info requests to High
• Update .NET Core runtime to 3.1.11
• Update BLE GW firmware to version 55.2.0

Fixed

• MT/MT2 API reconnect issue (MQTT backend)
• Unable to handle route depth 11
• Report correct hardware version for gateway to Management
• Gateway gets stuck at startup requesting gateway status using legacy MT11
• Firmware download from Management sometimes fails

3.4.1 - 2020-12-04

Changed

• Revert serial port library version

Fixed

• Serial port not working

3.4.0 - 2020-12-03

Added

• Generate '81.12 - Storage Mode Event' when device is in storage mode
• MT2 API: New topic mt/gateway/{g}/device/{d}/dfu
• MT2 API: Version number set to 1.0.0 (removed beta)

Changed

• Update .NET Core runtime to 3.1.10

Fixed

• Set unreachable = true for RSSI updates from devices in DFU mode
• Management fixes
• Use correct version of libnserial

3.3.0 - 2020-11-26

Added

• New property: 82.21 - RSSI Reporting (default value: 0x01)

Changed

• BLE Dongle firmware updated to version 55.1.0

Fixed

• Increase suppress interval for heartbeat/measurement/event sequence number from 10 seconds to 40 seconds. This is done to avoid getting duplicate heartbeats.
• Handle writes to 81.22 - Firmware Update Control property. Only apply is currently supported.
• Improve checks related to gateway properties

3.2.0 - 2020-11-19

Added

• MT2 API: Added broadcast write topic - mt/gateways/write/{identifer}

Changed

• MT2 API topic structure. New MT2 version number: 1.0.0-beta.3
• MT2 API: Let value for property write be optional

Fixed

• MT2 API: Require lowercase MAC and identifier in topics
• Device Management fixes

3.1.0 - 2020-11-16

Changed

• Location of config files related to Device Management has been changed
• MT2 API topic structure. New MT2 version number: 1.0.0-beta.2
• Firmware update performance enhancement
• Removed writing to system log for every outgoing MT message
• BLE Dongle Firmware updated to version 55.0.1

Fixed

• Firmware download via Device Management
• Firmware downlaod via Diagnostics

Added

• Property throttling support
• MT2 API: Added support for property cache flush

3.0.2 - 2020-11-05

Fixed

• MQTTnet downgraded to 3.0.12. This should fix TLS connection issue.

3.0.1 - 2020-11-05

Fixed

• Potential error when loading of firmware zip file.

3.0.0 - 2020-10-30

Changed

• New generic MT messages. Gateway BLE dongle firmware will be automatically upgraded.
• MBE backend API updated to 3.3.0
• Gateway configuration is now a set of property values, just like a normal BLE device.

Added

• Meshtech Device Management (iot.meshtech.no)
• MT2 backend API
• Firmware download via diagnostics/HTTP

Removed

• All gateway configuration parameters, except 'reportAll' have been removed. reportAll is converted to property 82.20 - Property Throttling Control
• Throttling of data has been removed

2.9.2 - 2020-05-29

Fixed

• Meshtech.Gateway 2.9.2
  • Fixed bug that caused device map command to fail

2.9.1 - 2020-05-27

Changed

• Meshtech.Gateway 2.9.1
  • Changed serial port library to libnserial

2.9.0 - 2020-04-28

Added

• Meshtech.Gateway 2.9.0
  • MBE API: Report Network Lock byte
  • Diagnostics API:
    • New command: device/3bit/switch
    • Added Mode column to output from device/3bit/list
  • MT API: New commands:
    • set-profile
    • get-profile
    • switch-mode
  • MT API: New reporting:
    • noise
    • co2

Changed

• Meshtech.Gateway 2.9.0
  • Update MqttNet to 3.0.9
  • MT API: Removed lastChanged property from motion reporting json payload
  • MT API: Updated version number to 1.0.0-beta.5
  • Diagnostics API:
    • Updated version number to 1.0.0-beta.8
    • Removed force optional parameter from device/ping/route

Fixed

• Meshtech.Gateway 2.9.0
  • Remove sequence number when device is switched from Unconnected to Connected mode
  • Do not add a dummy node to network tree when MT20 (disconnect) received

2.8.0 - 2020-03-30

Changed

• Dotnet-runtime updated to version 3.1.3
• Switched serial library to System.IO.Ports
• Removed AccessIO

2.7.1 - 2020-03-25

Changed

• Meshtech.Gateway 2.7.1
  • Updated Meshtech.MBE.API.Gateway to version 3.0.3.
• Meshtech.GatewayDeamon 2.1.0
  • Device certificate now only required when update server enabled
• aspnetcore-runtime updated to 2.1.17

2.7.0 - 2020-03-17

Added

• Support for Q100 hardware
• Meshtech.Gateway 2.7.0
  • Report beacon hardware version when beacon reports status

Changed

• Upgraded Yocto to Zeus release
• Meshtech.Gateway 2.7.0
  • Updated Meshtech.MBE.API.Gateway to version 3.0.2.
  • Telnet/diagnostics: config/gateway/reload moved to config/reload
  • Updated Diagnostics API version to 1.0.0-beta.7
  • Updated Vestrum API version to 1.0.0 (removed beta)
  • Use full-jitter exponential back-off algorithm when reconnecting to backend. Min. back-off: 1 second. Max. back-off: 10 seconds. Previous implementation used no randomization and had min. back-off: 100 ms, max. back-off: 10 s.

Fixed

• Meshtech.Gateway 2.7.0
  • MBE API: Various fixes for TCP connectivity, both TLS and non-TLS

2.6.0 - 2020-02-13

Changed

• Meshtech.Gateway 2.6.0
  • Updated Meshtech.MBE.API.Gateway to version 3.0.0. NOTE: MBE must be updated to major version 3
  • MBE: GetRelayEntries request now uses GUID as correlation id
  • Diagnostics: Dropping nested result objects for simple results
  • Telnet/diagnostics: Make date format consistent (ISO format)
  • Telnet/diagnostics: Model column from /device/mode/storage/list command is now model number (in hex)
  • Telnet/diagnostics: Model column from /device/3bit/list command is now model number (in hex)
  • Telnet/diagnostics: Added ModelName column to /device/mode/storage/list
  • Telnet: Added disableAuthentication option to telnet configuration
  • Updated Diagnostics API version to 1.0.0-beta.6

Fixed

• Meshtech.Gateway 2.6.0
  • NullReferenceException when handling set lock response
  • Exceptions on telnet 'quit' command
  • Firmware image files could be read from other locations than /tmp/mtgw

Component	Version
Meshtech.Gateway	2.6.0
Firmware (03)	53.2

2.5.0 - 2020-02-10

Changed

• Meshtech.Gateway 2.5.0
  • Enforce MT31 message sent using device/mode/mt31 command to be sent to gateway/root device only
  • Updated Diagnostics API version to 1.0.0-beta.5

Fixed

• Meshtech.Gateway 2.5.0
  • Diagnostics API: Provide proper error message when command was not found
  • Telnet/diagnostics Fix casing of headers in system/ethernet response
  • Telnet: Improve description for dfu/upgrade command

Component	Version
Meshtech.Gateway	2.5.0
Firmware (03)	53.2

2.4.0 - 2020-02-07

Added

• Meshtech.Gateway 2.4.0
  • Support for doing firmware upgrade using .zip file
  • Support for 'legacy' and 'secure' type DFU when using .zip file for upgrade. This is needed when upgrading unconnected devices (i.e. wristbands)
  • Support for sending MT31 message to unconnected device (i.e. wristbands) to switch them into DFU mode. This is only needed for "old" firmware that does not support the general "switch device mode" command.
  • Support for triggering update of unconnected device (i.e. wristbands) directly from gateway using 'legacy' and 'secure' methods. This can be used to automate update of such devices without using a phone app.
  • Telnet/diagnostics: Add mtlinux/reboot command
  • Telnet/diagnostics: Add system/ethernet command
  • Telnet/diagnostics: Add system/hostname command

Changed

• Meshtech.Gateway 2.4.0
  • Updated Diagnostics API version to 1.0.0-beta.4
  • Make sure updating of config files is done in a fail-safe way
• Updated BLE gateway firmware (Model 03)

Fixed

• Meshtech.Gateway 2.4.0
  • Some exceptions were not written to console
  • Telnet/diagnostics: Fix debug/stat output
  • Diagnostics: Postpone first ping message a bit

Component	Version
Meshtech.Gateway	2.4.0
Firmware (03)	53.2

2.3.0 - 2020-01-29

Added

• Meshtech.Gateway 2.3.0
• Telnet/diagnostics: Added support for performing legacy and secure DFU for unconnected devices.
• Telnet/diagnostics: Added support for listing 3-bit devices

Changed

• Meshtech.Gateway 2.3.0
• If some packets are lost when getting whitelist entries, missing entries are requested automatically.
• Getting whitelist entries now only supported for beacons supporting whitelist count validation
  • Model Number 0: 55.1+
• Telnet/diagnostics: Grouped commands related to 3-bit devices
• Updated Diagnostics API version to 1.0.0-beta.3
• Updated BLE gateway firmware (Model 03)

Fixed

• Meshtech.Gateway 2.3.0
• MBE API: GpioPinConfig.Unchanged not handled correctly when sending response
• Some MT messages caused "last-seen" to be updated incorrectly
• Some MT messages caused internal devices representations to be created when they should not.
• Getting whitelist entries might return incorrect number of entries

Component	Version
Meshtech.Gateway	2.3.0
Firmware (03)	53.1

2.2.0 - 2020-01-23

Added

• Meshtech.Gateway 2.2.0
• MT API: Add support for gnss reporting

Changed

• Meshtech.Gateway 2.2.0
• Changed algorithm of finding closest beacon. Determine beacon based on latest observations instead of last 30 seconds.
• Updated MT API version to 1.0.0-beta.4

Fixed

• Meshtech.Gateway 2.2.0
• Unhandled exception when switching device mode and no route to device was found
• RelayActivated event to backend can be triggered before beacon MAC address is known
• MBE API: When getting all whitelist entries fails, an unhandled exception occurs, resulting in no response to backend.

Component	Version
Meshtech.Gateway	2.2.0
Firmware (03)	52.0

2.1.0 - 2020-01-21

Added

• Meshtech.Gateway 2.1.0
• Vestrum API: Add battery and rssi reporting. Add support for reportrssi command.

Changed

• Meshtech.Gateway 2.1.0
• Reconnect backoff-ladder for diagnostics changed from [5, 10, 30, 60, 300] to [0, 5, 10, 20, 40, 60] (seconds). Thus, maximum reconnect interval is changed from 300 seconds (5 min.) to 60 seconds.
• Diagnostics API: Model number included in response to /device/mode/storage/list command. Listed when available.
• Updated Diagnostics API version to 1.0.0-beta.2
• Updated Vestrum API version to 1.0.0-beta.3

Fixed

• Meshtech.Gateway 2.1.0
• Diagnostics connection breaks when reloading config

Component	Version
Meshtech.Gateway	2.1.0
Firmware (03)	52.0

2.0.2 - 2020-01-17

Fixed

• Meshtech.Gateway 2.0.2: Fix diagnostics ping

Component	Version
Meshtech.Gateway	2.0.2
Firmware (03)	52.0

2.0.1 - 2020-01-16

Fixed

• Meshtech.Gateway 2.0.1: GetRelayWhitelistEntriesResponse to MBE backend does not handle ignore value for InProximityDelay.

Component	Version
Meshtech.Gateway	2.0.1
Firmware (03)	52.0

2.0.0 - 2020-01-15

Initial release.

Component	Version
Meshtech.Gateway	2.0.0
Firmware (03)	52.0