Version history

Version 1.5.9 (2026)

Serial Router: Added support for FT-450 CAT compatible protocol.

Displaying current config file name in Title.
Added custom protocol handler responses.
Fixed intermittent bug: service issue when right panel is enabled and sleep event occurs.
Few UI tweaks and fixes.
Wait for complete data transformer: Start marker can now be combined with Fixed data size.
Binary Splitter transformer: Start marker can now be combined with Fixed data size.
Monitoring tool: loaded monitoring file is now displayed in a separate window.
Added Finnish language translation.
TcpServer/TcpClient: added "Disable TCP buffering" configuration option (unchecked by default). It can improve network latencies in some scenarios.
TcpServer/TcpClient: replaced configuration controls with property list.
TcpServer/TcpClient: optimizations when sending modem registers status.
Log files are now in unicode format.
Fixed bug with "Persist window position" setting.
Fixed TcpServer/TcpClient monitoring bug on modem register change.
Added Text Responder transformer.
Added Binary Responder transformer.
Text data lines splitter: added custom separator mode.
Bridge device page: fixed transformer buttons font.
Quick config share device with Serial Router: added "Always keep RTS on" checkbox which is useful for TSxxx and FTxxx CAT protocols.
Adjusted tooltip delay time for all controls.
Logging error if failed to update license key.
Serial Router config page: display selected data protocol handler.
TcpClient: added configuration setting "Notify about connection errors".
TcpClient: added configuration setting "Virtual COM port must be fully connected".
Fixed few bugs which could cause stability issues.
Serial Router settings: fixed inconsistency for non-existing target COM port name.

Version 1.5.8 (January, 2026)

On close, displaying message if current configuration was modified (configurable in program settings)
Added "Quick config" wizards to context and main menu
Added "Create many connectors" quick config scenario
Added "Share COM port with Splitter" quick config scenario
Added "Share device with Serial Router" quick config scenario
Added "Share COM over network (TcpServer)" quick config scenario
Added "Share COM over network (TcpClient)" quick config scenario
Added "Minimize on startup" option in preferences
Serial Router: Added support for FT-897 CAT compatible protocol
Serial Router: Added support for FT-920 CAT compatible protocol
Added service settings tab to Preferences window
Service settings: added "Autostart config enabled" option (enabled by default), now autostart can be disabled without deleting autostart config
Service settings: added "Handle power events" option (enabled by default), the emulation is stopped on suspend event and started on resume event
Mapper device has been deprecated, recommended replacement: Redirector + Connector
Added "Delete license key" menu command
Added "Load autostart config", "Delete autostart config" and "Autostart" menu commands
Property list control: supporting multiline tool tips
Property list control: added Description panel
Terminal and Bridge COM port data source: supporting COM port names like "1" and "COM1"
Terminal: added cooldown before trying to reconnect
Terminal: connect automatically after selecting new data source
Fixed bug: devices list redraw issue during column resize
Command line: added start_device, stop_device and restart_device parameters
COM port settings: added "Allowed to read data", "Allowed to write data", "Allowed to modify RTS", "Allowed to modify DTR" options
Monitoring tool: added Exact Match checkboxes for Device and Object
Command line: added create_device support
Fixed bug: invalid bottom panel size when starting minimized from command line
Open with Terminal: added additional COM ports for all devices
Serial Router: added support for custom protocol initialization string
TcpServer, UdpManager: added "Test connection" button which invokes Windows Firewall popup window and simplifies setup
Fixed bug: Redirector configuration Test button for port 2 was not working properly
Information panel: Added COM port information for some devices
All devices: displaying current COM port settings in settings dialog
Transformers buttons now have bold text if not empty
Fixed bug: When manually loading autostart config from menu, configuration title and description were not properly updated
Many UI tweaks and fixes
Fixed compatibility with some applications

Version 1.5.7 (August, 2025)

Pair device: added "Number of lanes" parameter which significantly simplifies configuring multiple 3rd party apps with Serial Router
Serial Router: added support for FT-710, FT-991, FT-950, TS-690 and TS-870 CAT compatible protocols
Serial Router: automatically connecting to all lanes when one of target ports is Pair device with multiple lanes
Serial Router: start time significantly improved
Added drag and drop support to VSPE application for loading config file
TcpServer, TcpClient: added "Read and discard stale data from COM port" option (enabled by default) to avoid buffering stale data if TCP connection not established
Displaying error message for selected device in status bar (such as TcpClient failed connection status)
Added device error message in the device list Status column
TcpClient: logging connection error messages to log file
Device Create Wizard: on failure, the device is created in Stopped state
Device Create Wizard: specifying optional device Title and Description on first page
Device Properties: added Description tab
Lots of user interface improvements such as resizable windows, default selections, tab navigation etc
Message view: limiting number of displayed messages, optimized adding new messages
Max log file size is now limited to 8 MB
Terminal: modem registers changes are displayed much faster when Quick Update mode is enabled
Terminal: added "immediate send mode" checkbox
TcpServer, UdpManager: added button to check current Windows Firewall settings (checking allow/block rules for specified TCP/UDP ports for VSPE service)
TcpServer, UdpManager: added suggested PowerShell command to add inbound allow rule to Windows Firewall for specified TCP/UDP ports
Test COM port tool: skipping configuring COM port with default settings on port open
Improved compatibility with certain applications
Stopping TcpClient and Bridge TcpClient is much faster during connection attempt
Stopping TcpServer with connected clients is much faster
TcpServer: optimized handling client connections
Fixed bug: "Sent data" column was reporting wrong value (x2) in Connector,Pair and Splitter devices
Fixed bug: Terminal not displaying new data after clearing window if the previous data is the same
Fixed bug: INF processing error during VSPE install after using certain disk cloning software
Fixed bug: Occasionally, the application could not be properly closed
Fixed bug: Fixed rare race condition in Splitter when ReadTotalTimeout was not properly processed
Fixed bug: Fixed handling PURGE_RXABORT request

Version 1.5.6 (June, 2025)

Serial Router: added support for TS-570 CAT compatible protocol
Added Compress/Decompress data transformers which can be used to reduce network traffic
Added Encrypt/Decrypt data transformers (symmetric AES256 encryption)
Added "Write to file" transformer
Added "Minimize to system tray" option in preferences
Transformers collection: added PostDelay property for controlling data buffer (useful for Compress transformer)
Transformers collection: fixed bug with default Help button
Transformers collection: fixed UI bug when moving transformers up and down
Fixed issue when loading config file with non-existing transformer (forward compatibility)
Connector, Splitter, Pair: added "Purge buffers" on open and close settings
COM port settings for user-mode devices: added "Purge buffers on open" setting
Fixed bug: new license key is not properly stored when license file from old version already exists
Fixed bug: TcpServer transformers to COM port were not unique for every connection
Fixed bug: Connector/Splitter did not work properly with apps like AutoHotKey which write data and immediately close COM port
Fixed bug: Bridge COM port could not be properly parsed when in lowercase (i.e. com1)
Not displaying error message when loading configuration and device switches to Waiting state
When starting another VSPE instance, show VSPE window which is already running
VSPE cmd line: when starting another VSPE instance, transfer cmd line to VSPE which is already running
Device context menu: Restart device command

Version 1.5.5 (May, 2025)

Serial Router: added TS-450, TS-850, TS-950 compatible CAT protocol support
Localization: added translations to more languages
User interface: Added more tooltips
Splitter: "Allow buffer overruns" renamed to "Not allowed to block read flow" which explains it better
Help window: Removed "always on top" style
Added VSPE application setting: Delete all devices on close (disabled by default)
Added Help -> Show license key menu command
Added checkboxes with options to application close confirmation dialog

Version 1.5.4 (April, 2025)

Splitter: fixed read data delay on first client connection when "stop reading data" checkbox is set
Virtual Pair and Virtual Splitter: added support for overriding serial timeouts. Useful for non-trivial scenarios with some applications.
UdpManager: added broadcast/multicast mode
TcpServer/TcpClient: added support for TLS or mTLS auth (optional)
TcpServer, TcpClient, Bridge: managing TCP Keep-Alive packets interval in settings
TcpServer/TcpClient: fixed (rare) race condition when forwarding modem registers fails
TcpClient: immediate reconnect delay changed to 1 second
TcpClient: Fixed bug when settings cannot be changed when device is in Connecting state
Fixed bug: invalid StopBits value when loading legacy config file created by VSPE with version older than 1.2
Serial port settings: added additional write-specific settings
Serial Router: removed "Buffered read mode" checkbox because it was moved to Serial port settings
Serial Router Switch (ICOM compatible protocol): Added support for broadcast responses with id=1
Serial Router: added FTDX-1200,FTDX-3000, FTDX-9000 compatible CAT protocols support
Serial settings dialog: allowing entering custom COM port speed
Binary transformer (include/exclude): added support for multiple filters with attributes (offset_abs)
Binary transformer (include/exclude): added support for placeholder values
Fixed delay when writing to COM port for the first time in another thread for some devices like TcpClient
Monitoring tool: added data include/exclude filters
Monitoring tool: added "color highlight" mode
Monitoring tool: added toolbar and menu
All dialogs show context help on F1 key press
Added tooltips to device configuration pages

Version 1.5.3 (March, 2025)

Based on feedback, Autostart config option was removed from preferences and replaced with "File->Save as autostart config (on VSPE service startup)" menu command
Supporting configuration file names with unicode characters
Supporting installing to folder with unicode characters
Added optional settings for restoring window position, size, columns, panels
Added "View" menu to show/hide right and bottom panels
New transformer: Wait for complete data
Fixed transient "Error" state for newly created kernel devices
Serial Router: added global write and read transformers
Serial Router: fixed "allowed to read" option for target port
Serial Router (ICOM compatible protocol handler): handling broadcast packets from radio station
Serial Router: added support for FT-891 CAT compatible protocol
Transformers: fixed race condition in "multiple writers" scenario
Bridge (TcpClient): fixed race condition on shutdown during active traffic
Connector/Pair: fixed rare race condition when waiting for multiple comm events
Connector/Pair: added "Reset modem registers on close" option (off by default)
Connector/Pair: added "Always queue write requests" option (off by default)
Serial Router: fixed initialization sequence priority when placed before Splitter it depends on
Serial Router: UI improvements in settings
Serial Router: added FT1000 CAT compatible protocol (in SmartRouter mode)
Serial Router: added additional validation for requests/responses in supported protocols
Splitter, Serial Router: added experimental "Buffered reading mode" to reduce number of read/writes
Monitoring tool: added GetCommProperties, GetCommTimeouts, SetCommTimeouts events
Terminal: Added "Query debug info" command for COM port
Terminal: Added "Send byte by byte" checkbox
Terminal: fully async Send requests
Added simple "Test Com Port" tool for investigations
Virtual ports: fixed CurrentTxQueue, CurrentRxQueue reporting
Terminal: fixed resizing bug with Copy button
VSPE API COM Server: fixed dispatch interface, added Python and PowerShell examples
VSPE API: Switched to Free threading model
VSPE API: Added vspe_runMaintenanceRoutine method
VSPE API: Fixed vspe_getDeviceIndexByComPortIndex
TcpServer: fixed bug with memory leak on stopping device
TcpServer: fixed bug when not closing source COM after failing to start due to the network issue
TcpServer: added "Delayed initialization on network error" option
Serial Redirector: added "Waiting" state like other devices when misisng dependency
Immediately displaying Waiting state for devices which failed to start by request and switched to Waiting mode
Splitter: fixed readable/writable config options
Splitter: improved performance of write requests
Splitter: added support for hardware flow control (RTS/CTS) which can be defined in port settings
Virtual Devices: Received is now actual Received in Read request value (not total bytes copied to Input buffer like before)
Kernel device information panel: more information in RX/TX columns
Main window: Fixed received/sent statistics for all devices
Fixed sending delay for COM ports used in all user mode devices
Driver: Fixed long delay when sending data one by one with BaudRate emulation enabled and Read request is waiting for data at the same time
Connector/Pair/Splitter: better read/write timeouts handling
Connector/Pair/Splitter: releasing WaitCommEvent requests when SetCommMask is set to 0
All devices: COM port names now can be typed as a string COM1 or as number 1
Added "minimize" command line argument
All user-mode devices: limiting max COM port write chunk size to 128KB to avoid failures when sending too much data
All user-mode devices: more reliable write requests when sending lots of data

Version 1.5.2 (February, 2025)

Transformers: added Binary splitter and Binary filter transformers
Splitter: fixed read issue with some USB-to-serial adapters
Splitter: fixed rare condition with lost RXCHAR event
Splitter: added "Read using polling mode" config option
Splitter: readable/writable options for every virtual port
Splitter: overrun timeout value can now be specified in settings
Splitter: fixed delay on fast write after connect for the first client
Connector/Pair: (configurable) emitting EV_EVENT1 and EV_EVENT2 on peer connect/disconnect
Connector/Pair: fixed "ignore writes if partner not connected" option
Connector/Pair: write request is now async, and TXEMPTY event is emitted after request completed
Connector/Pair: (configurable) allow buffer overruns
Generating EV_RXFLAG event for Connector/Pair/Splitter devices
User-mode devices: fixed COM port initialization sequence which could cause not reading events when input buffer was full before initialization
TcpServer/TcpClient: added option to clear COM port input buffer on connect
TcpServer/TcpClient/UdpManager: fixed race condition issue on stop
Monitoring tool: added milliseconds to time stamps
Terminal: fixed freezing when having too many RX events without fast mode enabled
Terminal: fixed potential deadlock when preparing output data
Terminal: added "Copy" button to copy data to clipboard
VSPE license key dialog: supporting multiline (in case the license key formatting is broken)
VSPE installer: fixed ansi to unicode string conversion for VSPE shortcut which resulted in incorrect .vspe file description in Explorer
VSPE installer: supporting additional install/uninstall mode without VSPE kernel driver (useful in some scenarios)
Redirector, Serial Router: added "Detect stale incoming data" option when reading from COM ports which are constantly sending data (like GPS) and need to be re-initialized if the data flow stops
Fixed: race condition when stopping some VSPE devices
New VSPE device: Serial Router device with "FanOut" and "Smart router" modes
Serial Router (Smart router mode) - added support for certain CAT/rotator compatible protocols
Serial Router: added "Close if no connections" option to avoid keeping source port opened all the time
Fixed OmniRig startup timeout issue when connected to Pair/Connector
API: added startDevice, stopDevice methods

Version 1.5.1 (December, 2024)

Splitter: fixed bug with not emitting TXEMPTY event (now correctly works OmniRig)
Localization: added translations to more languages
VSPE devices: introducing delayed initialization for devices waiting for dependencies
Added custom descriptions for VSPE configuration and for VSPE devices
"Stopped" and "Started" device states are persisted in VSPE config file
Added Monitoring tool: monitoring traffic for VSPE user-mode devices
Supporting additional command line parameters (start, stop, close)
Serial settings: removing DTR/RTS line enabled settings - instead switching to classic Handshake types
Serial settings: initial DTR/RTS modem registers state now have 'Not defined' state
Splitter: separate settings for controlling RTS/DTR forwarding
Splitter: added setting "Only first connected client can write data and update modem registers"
Splitter: modified writing to source COM port flow to reduce the likelihood of conflicts
Connector/Pair: fixed bug with losing events on re-connect
Connector/Pair: added setting to ignore write events if partner not connected
Connector/Pair: added support for custom RTS/DTR pinouts
Splitter: added setting to stopping reading from source COM port when no clients connected
Splitter: added setting to reset RTS/DTR when no clients connected
Splitter: added setting to clear input buffer when no clients connected
Splitter: fixed bug with sending multiple write requests sequentially to source COM port
Terminal: fixed bug with freezing
TcpServer/Client/Redirector: fixed bugs with initial forwarding or modem registers
Fixed UI bug in serial settings selection for Stop Bits property
Lots of UI changes for colors consistency, keyboard navigation, focus etc.

Version 1.5 (November, 2024)

Virtual ports are now visible in Device Manager and to all applications
VSPE service (running with minimum privileges on local computer) is now automatically loading last known configuration on startup (if enabled in settings)
Native ARM64 platform support
Introducing transformers for user-mode devices to filter/modify/control consistency of the data flows
Virtual Splitter device: legacy mode with single shared virtual port or new mode with multiple virtual ports for better data flow control
Fixed unicode characters localization and added new languages
All kernel devices: fixes for Read/Write timeouts, supporting additional serial port events
Virtual Splitter: internal data flow is fully re-written to make Splitter more reliable
Virtual Connector/Pair: fixed baud rate emulation, resetting DTR/RTS registers on disconnect
Virtual Splitter/Connector adding option to limit connections from the same application to the same virtual port
Redirector, UdpManager, TcpServer, TcpClient, Bridge (Serial Port): switched to async read mode for better performance
Transformers: Added LineSplitter and TextFilter transformers, adding multiple transformers for all supported user-mode devices
Bridge: added NamedPipe client/server
Serial Redirector: fixed issue with incorrect settings for device 2
Serial Redirector: added read-only options for COM ports
UdpManager: added read-only and write-only settings for COM port
User interface: Added Start/Stop/Clone commands for devices
User interface: "Open with terminal" menu now works for all virtual ports and TcpServer
User interface: Terminal: fixed new lines, scrolling
User interface: COM port selection drop list is now correctly pre-filled with existing COM port names
Installer: validating for x32 platform installer when installing on x64 operating system because it caused driver installation issues
Removed non-relevant settings (delete devices on quit, set as service helper etc) and command line parameters
Deprecated: HttpServer is deprecated and removed
Removed kernel devices data flow monitoring (it will be replaced with better monitoring solution in future version)
VSPE documentation is fully re-written
TcpServer: fixed bug with not setting keep alive settings for connected sockets
TcpServer: added option to Close/Open COM port based on TCP connection state (number of connected clients)
TcpServer: added maximum number of connections configuration setting
TcpClient: fixed reconnection timeout setting
TcpClient, Bridge: moved connection logic to separate thread to avoid lag when creating device
TcpServer, TcpClient now can have only modem registers control connections (no data connections)
Bridge file data source: input file is opened with share write permissions, allowing input file to be updated
Bridge file data source: added option to read file from end
Allow editing any device in Running state (unless it is a kernel device with active connections)

Version 1.4 (June, 2024)

This is the last version with current driver install model, next version will have significant changes.
(Experimental) VSPE COM ports visible in Device Manager (experimental feature, enabled in settings, fixes some apps, work is still in progress)
Introduced initial DTR/RTS states in serial port settings
Fixed initial DTR/RTS states for TcpServer and TcpClient depending on connection status
Removed deprecated python 2.7 python bindings
Added buffer size in Bridge configuration (Tcp flow)
Bridge device: not displaying error if initialization failed, allowing it to re-connect
Fixed ReadIntervalTimeout kernel driver bug
UdpManager: fixed receiver with packet size > 1024
Keyboard navigation UI fixes
Few UI tweaks and improvements

Version 1.3 (July, 2023)

Improved Connector/Pair kernel driver performance
Startup properties tab in Preferences
Fixed "Stop bits" bug in serial port settings
Improved logging
TcpClient/TcpServer: control data port to propagate modem registers
UI fix for inconsistent serial port selector
Fixed modem redirection logic for Serial Redirector
Fixed kernel driver race condition for Connector/Pair devices

Version 1.2 (January, 2023)

Windows 11 on ARM64 kernel driver is part of x64 build now
Fixed lots of kernel driver stability issues for x64 versions (Win10 and Win11)
VSPE Windows Service is now working for all devices (not compatible with previous version, service needs to be re-created)
VSPE Service mode: silent mode
Bridge: read-only mode for data stream
Bridge: added Text Transformer (replacing regex/wait for new line with separator)
Bridge: added Binary Transformer (replacing data/wait for new data chunk)
More control over serial port settings
Numerous bug fixes
Added simple Terminal tool
Spy: better descriptions, n/a stream is now supported
Added more technical details to Help->About
More detailed error descriptions
UI fixes and tweaks