# Firmware release notes

## YuDash V5.5

* Release date: 18 September 2025
* FTP enhancements
  * Generic string in case of error
  * Support of variable specific formatting (decimals in floating point numbers) 
* Payload Enhancements
  * Flexible JSON (JSON\_19) payload based on input format
  * Generic timestamp encoder besides standard timestamps
* Support of Jal Jeevan Mission API servers
  * 250+ group register read.
  * Complex payload structure with boolean outputs and metadata 
  * Available as licensed version.
* Weather monitoring Features. 
  * Available in LYNX80 and FELYX80 series
  * RS232, SDI12 and rain gauge

## YuDash V5.4

1. Release date: 26 June 2025
2. **YuDash Axon:** 
   * [**YuDash Axon**](/dc/df/axon.md) is the edge intelligence layer built into **YuDash IoT devices**, designed to preprocess data at the device level before forwarding it to the cloud or industrial systems.
   * Includes [**YuParse** ](/dc/df/axon/parse.md)engine for generic string parsing based on tokens.
   * **YuCalc** : generic real-time calculation engine (planned in later release).
   * **YuDash Axon feature is license based feature available in specific premium models.**
3. Modbus Enhancements
   1. Modbus/RS485 bank register read and output as string/JSON array.
   2. Support of **instantMqtt** feature with non-persistant MQTT connection. Applicable for specific Government server.
   3. Modbus RS485 coil write bugfix in Modbus server.
4. Payload enhancements
   1. Support of metaData in JSON\_10 payload format. The key-value pairs in **metaData** block in payloadSettings will be passed to output payload besides telemetry data.
   2. Support of parsing device data in all payload formats
   3.
5.  
6. grouped register read
   1. Support of group modbus read and Added support to read up to 64 registers in a single group (instead of individual register reads) over Modbus/RS485.
   2. This is implemented through `slaveType` encoding.
   3. After the banked read, individual registers can be parsed using specific data types.
   4. This enhancement improves Modbus response time and addresses limitations in certain field instruments.
7. Modbus/RS485 Master register bank read: 
   1. Up to 100 Modbus registers can now be read as a sin

## YuDash V5.3

1. Release date: 18 May 2025
2. Modbus/RS485 grouped register read
   1. Added support to read up to 64 registers in a single group (instead of individual register reads) over Modbus/RS485.
   2. This is implemented through `slaveType` encoding.
   3. After the banked read, individual registers can be parsed using specific data types.
   4. This enhancement improves Modbus response time and addresses limitations in certain field instruments.
3. Modbus/RS485 Master register bank read: 
   1. Up to 100 Modbus registers can now be read as a single string.
   2. A maximum of three register banks can be read from the PLC.
   3. Register values can be encoded in string as as:
      1. 16-bit signed integers
      2. 16-bit unsigned integers
      3. Hexadecimal values
   4. This feature is available in the JSON\_10 and TEXT\_21 payload format.
4. MQTT to Modbus Server enhancement
   1. MQTT subscribe-to-Modbus-server (slave) functionality is now supported.
   2. Supports mapping of up to 64 variables to Modbus registers (increased from 32).
   3. Supported data types:
      1. 16-bit signed intege
      2. 32-bit floating-point
   4. A notional “Modbus timeout” mechanism is added. If MQTT subscribe commands are not received for a set number of cycles, mapped values revert to a default value.
5. YuDash Setu Features are incorporated:
   1. MQTT to Modbus write feature when YuDash is Modbus master.
   2. yudm:  YuDash device management APIs through dedicated MQTT topic.
6. TCP Parser enhancements
   1. Support for upto 24 tags in TCP parser.
   2. Support of "status" variable to identify working tags in TCP parser. This useful when multiple tags of same name are present.  
7. Sub Firmware Versions:
   1. V5.35:  YuDash LYNX
   2. V5.30: YuDash ZENYX 

## YuDash V4.6

1. Release date: 14 November 2024
2. Enhanced Ethernet setup and retry feature to check ethernet link status. This is primarily applicable for on-premise and peer-to-peer communication.
3. SD card Data logging with "useDefaults" feature. 
   1. With useDefaults enabled, SD card logging will be enabled all parameters (maximum 16) with first column as timestamp. The logger file is created on per-day basis in directory "/logger\_dir".
   2. User can provide partial settings and other parts will be taken as default.
4. Bugfix of variables clash when both Lan UI and Modbus server is enabled.
5. Support of upto 20 variables in Modbus server.
6. Support of upto 30 variables in LAN UI server.
7. Beta version of serverMode. 
   1. serverMode is applicable with timeSync feature along with YuDash device acting as Modbus server.
   2. The input instruments are read continuously for real-time refresh to Modbus server. This is similar to loopDelay=0.
   3.  Data push to cloud and SD card logging is done as per timeSync value. 
8. Sub Firmware Versions:
   1. 4.62:  YuDash LYNX
   2. 4.60: YuDash ZENYX
   3. 4.67Q: YuDash LYNX with Quectel 4G module.
   4. 4.65Q: YuDash ZENYX with Quectel 4G module 

## YuDash V4.5

1. Release date: 13 October 2024
2. Enhancement for SD card mounting error and retries.
3. Enhanced Modbus RS485 server to avoid read errors.
4. Sub Firmware Versions:
   1. 4.52:  YuDash LYNX
   2. 4.50: YuDash ZENYX
   3. 4.57Q: YuDash LYNX with Quectel 4G module.
   4. 4.55Q: YuDash ZENYX with Quectel 4G module 

## YuDash V4.4

1. Release date: 1 August 2024
2. Support of SSL/TLS in MQTT and HTTP communication.
3. Firmware upgrade feature over local WiFi (OTA).
4. Improved SD card interface through repeated mounting attempt at bootup.
5. Improved configuration UI. Assets files can be browsed and updated.
6. Sub Firmware Versions:
   1. 4.42:  YuDash LYNX
   2. 4.40: YuDash ZENYX
   3. 4.47Q: YuDash LYNX with Quectel 4G module.
   4. 4.45Q: YuDash ZENYX with Quectel 4G module 

## YuDash V4.2

1. Release date: 8 May 2024
2. Support of LAN based configuration server and device monitoring.
3. Advanced text payload encoder.
4. Generic FTP support for text/CSV payload and file name.
5. High precision 16bit 8 channel ADC (Analog to digital converter) for LYNX.
6. Data logging on local SD card in generic CSV/text file format. This logging is independent of cloud payload.
7. Sub Firmware Versions:
   1. 4.22:  YuDash LYNX with 16 bit ADC
   2. 4.20: YuDash ZENYX

## LYNX V3.9

1. Release date: 23 January 2024
2. Support of resetting to factory defaults in configuration page.
3. Support of SD card deletion from configuration parge.
4. Modbus RS485 with 115200 baud-rate through hardware Serial.
5. Two Register read in Modbus RS485 for single register read. varType of 60-69 has been added to support specific limitations in flow instrument.

## LYNX V3.7

1. Release date: 11 November 2023
2. Enhanced HTML parsing and tag search per updated [documentation](/yudash-iot-devices/lynx-user-manual/lynx-settings/html-parser-settings.md).
3. Support of DS18B20 temperature sensor.
4. Improved MQTT reconnect check to maintain connection with server.
5. Beta feature of MQTT to Modbus/RS485 slave (server). This acts as remote Modbus server. 

## LYNX V3.6

1. Release date: 13 October 2023
2. Enhanced Modbus read support for 32 bit registers:
   1. Support for byte swapped registers for LSB and MSB using 3 digit code. 
   2. Support for unsigned-int for 32 bit Modbus registers (code 24, 25) 
   3. Now YuDash IoT gateways support all byte swapping ([Modbus documentation](https://docs.yudash.com/yudash-iot-devices/lynx-user-manual/lynx-settings/modbus-rs485#h.jt0n9eorg4hg_l)) 
3. Support for Float64 and Int64 register read in Modbus. This is subject to data handling at 32 bit during transmission.
4. Support for 8 channel analog in LYNX48 (V3.61)
5. Bug-fix in SD card read during NFH (network failure handler) operation.

## LYNX V3.5

1. Release date: 15 September 2023
2. Addition of JSON\_FORMAT\_16 payload format. 
   * This is applicable for Indian OEM customer.
3. JSON\_FORMAT\_17 and JSON\_FORMAT\_18
   * Generic two level JSON payloads with array (17) and JSON (18)
4. Improved reliability of temperature Digital Sensor DS18B20.
5. Firmware variant V3.51 for LYNX48 data logger with 8 channel analog inputs.

## LYNX V3.4

1. Release date: 2 August 2023
2. Improved HTTP/SSL support.

## LYNX V3.2

1. Release date: 16 June 2023
2. Addition of JSON\_FORMAT\_14 and JSON\_FORMAT\_15
   1. Metadata at device level and variable level in JSON payload.
   2. Variable mapping option in payload
3. Support of multiple cloud servers (upto 6 servers) for HTTP and FTP. 
4. Addition of timestamp format: TS\_55 and TS\_65 (YYYY-MM-DD HH:MM:00)

## LYNX V3.1

1. Release date: 29 May 2023
2. Support of payload type XWWW\_FORMAT\_30 for *application/x-www-form-urlencode*d in HTTP/REST API Servers.
3. Improved watchdog timer.


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