Quick start
Install the app, find the COM port and complete the first successful send and receive.
Quick start
User Guide
Serial Port Utility User Guide
Choose one focused article for the task at hand. Each page keeps its own contents and related next steps.
User Guide
Set up a reliable connection
Start with the physical link, serial settings and workspace controls.
Serial connection parameters
Ports, baud rate, framing, flow control, line endings, Enter Sends and echo.
Serial connection parametersQuick Settings panel
Show, hide and reorder connection, receive and send controls.
Quick Settings panelIndicator lamps and control lines
Understand TX/RX activity, modem lines, DTR/RTS control and Break.
Indicator lamps and control linesText, Hex and encodings
Readable commands, binary frames, byte checks and the GB18030/GBK/Big5 encodings.
Text, Hex and encodingsBuild repeatable workflows
Automate commands, preserve evidence and verify protocol or network traffic.
Automatic send and command lists
Loop commands, send lists line by line and reuse send history.
Automatic send and command listsCommand library and sequences
Command buttons with shortcuts, and sequences that send, wait and check the replies.
Command library and sequencesAuto reply
Match text, hex, wildcards or regex and reply with a delay, a checksum, or not at all.
Auto replyScript automation (Lua)
Lua 5.4 scripts with send, expect and read, binary packing, over 50 checksums, onReceive to play the device, and three examples.
Script automation (Lua)Logs and long-running capture
Capture timestamped evidence and plan log rotation for long-running tests.
Logs and long-running captureSession recording and replay
Record sessions to .spulog with F9 bookmarks, then replay them with a timeline, search, loops and speed control.
Session recording and replayExporting data and the diagnostic pack
C arrays and hex dumps from a selection, session export to CSV or JSON Lines, and a diagnostic pack for support.
Exporting data and the diagnostic packCRC and Modbus checks
Check payload bytes, algorithm parameters, CRC byte order and raw responses.
CRC and Modbus checksProtocol decode view
A frame table for Modbus RTU / ASCII / TCP and custom frame templates, with field details, pairing and CSV export.
Protocol decode viewReal-time plot
Live curves from printf, VOFA+ FireWater, JustFloat or Arduino Serial Plotter output, with statistics and cursors.
Real-time plotTCP and UDP debugging
Debug TCP Client, TCP Server and UDP traffic alongside the serial link.
TCP and UDP debuggingRFC 2217 client
Drive a remote serial port, take over its parameters, or bridge it to a local port.
RFC 2217 clientFile transfer (XMODEM / YMODEM)
Update a device from its bootloader without a second terminal program.
File transfer (XMODEM / YMODEM)Live Sync: hand the port to someone else
The four peers under the status bar's Live Sync entry: open the port to the LAN, to a browser, to another machine of yours, or to a colleague with no account.
RFC 2217 server
Share this machine's serial port over TCP, with access control and server-side checks.
RFC 2217 serverWeb remote debugging with Live Console
Debug from anywhere with live viewing, remote send and port control through Live Console.
Web remote debugging with Live ConsoleRemote serial port with Live Relay
Share a port from the site -- desktop or headless -- and drive it from elsewhere as a real port.
Remote serial port with Live RelayLive Share (invite codes)
Share one port with a colleague who has no account -- in their application or straight in a browser.
Live Share (invite codes)Diagnose and get help
Work back from a symptom, or prepare the account and support details.
Troubleshooting checklist
Diagnose missing ports, open failures, resets, no data and unstable links.
Troubleshooting checklistRegister and activate
Account registration, sign-in activation, entering a key, offline activation and what comes after.
Register and activateRequest a refund
Which orders qualify, the Request refund button, the statuses a request moves through, and what happens to keys, traffic and invoices.
Request a refundOrders, activation and support
Orders, offline activation, Cloud Sync and the support evidence checklist.
Orders, activation and support