Connect & Configure
Open a serial port, verify the electrical interface separately, and begin in receive-only Monitor Mode.
Hardware access check
Checking Web Serial support…
Operating mode
Monitor — receive onlyMonitor Mode is safe by default.
LINEGLASS receives bytes but hides transmit controls. Transmit never unlocks automatically after reload or reconnect.
Before connecting
I verified voltage standard, pinout, polarity, and ground.
I will begin receive-only and avoid changing termination or biasing on a live network.
I am authorized to connect to this equipment.
Port A
Not connectedNo adapter selected
Arbitrary positive rates accepted by the adapter.
CTS
DSR
DCD
RI
Port B
Not connectedNo adapter selected
Quick start
1Verify wiring
2Connect adapter
3Start capture
4Choose framing
5Decode & chart
Live Capture
Capture raw bytes with host-arrival timestamps. Pausing the display never pauses recording.
Total bytes
0
Frames
0
Duration
00:00.0
Bytes / s
0
Frames / s
0
Line use est.
0%
Checksum failures
0
Storage est.
0 B
Raw data
Connect a serial adapter, import a capture, or deliberately load a demonstration.
Capture policy
Replay
Stopped0 / 0 events
Frame Builder
Transform arbitrary serial chunks into reviewable frames without losing the original bytes.
Framing rule
Add header/checksum bytes not counted by the field.
Rule test
Not testedFrames detected
—
Leftover bytes
—
Average length
—
Checksum success
—
Select or load data, then test a framing rule.
Frame inventory
0 frames| # | Time | Channel | Dir. | Length | Bytes | Decode | Integrity | Summary |
|---|
[ ]
No frames yet. Capture, import, or load a demonstration.Decoder Workbench
Apply a built-in decoder or define a reusable binary field schema.
Decoder
RawRaw interpretation preserves bytes and offers text, integer, and bit-level views.
Decode new frames automatically
Permit labeled direction inference with confidence
Protocol summary
Decoded
0
Valid integrity
0
Warnings
0
Unique commands
0
No decoded frames.
Custom binary schema
Supported field types
uint, int, float32, float64, fixed, ascii, utf8, bcd, hex, bytes, bits, timestamp, and enum. Fields can specify endianness, scale, offset, unit, mask, enumeration, and chart eligibility.
Schema has not been validated.
Visualization Workspace
Choose one coordinated view at a time. Charts use host-arrival time unless a capture bridge supplied hardware timestamps.
Activity Timeline
Host arrival timeLoad or capture data to visualize.
Explore Unknown Protocol
Cluster frames, align byte positions, test integrity candidates, and surface hypotheses without presenting them as facts.
Analysis scope
Frame clusters
Not analyzed∷
Run analysis to group messages by length, prefix, suffix, and similarity.Byte-position heatmap
Stability, change rate, entropy, and candidate roleNo aligned frame cluster selected.
Candidate fields
?
No hypotheses yet.Integrity explorer
No integrity test run.
Correlation explorer
Compared against 8-bit and 16-bit values at each aligned byte offset.
No correlation analysis run.
Repetition & periodicity
↻
Analyze frames to measure dominant periods, jitter, bursts, and idle windows.Baseline Comparison
Compare settings, message inventory, timing, ranges, and errors against a named baseline.
Baseline
NoneComparison summary
Not runAdded
—
Removed
—
Changed
—
Regressions
—
Create a baseline, then load or capture a comparison session.
Differences
| Classification | Area | Baseline | Current | Interpretation |
|---|
⇄
No comparison results.Transmit Workbench
Transmission is secondary to monitoring, disabled by default, and never restored automatically.
Transmit is locked.
Imported projects, reconnects, and page reloads cannot unlock it. Review the exact byte preview before sending.
Compose command
TX LOCKEDNo payload.
Finite repetition
Line signals
DTR, RTS, and break are hardware controls. They remain blocked until transmit is unlocked, and adapter support varies.
Saved commands
>_
No saved commands.Command history
| Time | Port | Bytes | Status |
|---|
→
No transmitted bytes.Sessions & Replay
Keep captures as durable local artifacts, deliberately load demonstrations, or import evidence collected elsewhere.
Demonstration captures
Sample data is never loaded into a new project automatically. Loading replaces the current unsaved capture after confirmation.
Current session
UnsavedSession ID
—
Started
—
Chunks
0
Frames
0
SHA-256 will be calculated during evidence export.
Locally saved sessions
▤
No saved sessions in this browser.Evidence Report
Produce a self-contained report with explicit limitations, hashes, statistics, selected frames, and analysis results.
LINEGLASS Evidence Report
Generate the report to populate current project and session evidence.
Settings, Hardware Guide & Limitations
Manage the local project and review the boundary between decoded serial bytes and electrical measurements.
Project
Display & storage
Storage estimate not requested.
Diagnostics
LINEGLASS initialized.
Hardware and wiring guide
RS-232 is not TTL UART
RS-232 uses different voltage levels and polarity than 1.8 V, 3.3 V, or 5 V TTL UART. Use an adapter designed for the target electrical standard. LINEGLASS cannot verify voltage compatibility.
RS-232 monitoring and direction
A normal receiver sees one signal direction. Passive monitoring of both directions generally needs a tap and two receive channels. A normal endpoint can reliably label bytes LINEGLASS writes as TX and bytes it reads as RX.
RS-485 two-wire, four-wire, polarity, termination, and bias
Two-wire RS-485 shares one differential pair for both directions; four-wire uses separate transmit and receive pairs. A/B labeling is not universal. Verify both equipment manuals. Do not add termination or biasing to an operating network without understanding its topology.
RS-422
RS-422 commonly uses separate differential transmit and receive pairs in point-to-point or multidrop arrangements. Confirm pair names and polarity from the equipment documentation.
Isolation and common reference
Galvanically isolated adapters are strongly preferred around industrial equipment, long cable runs, or uncertain ground potential. Even differential buses may have common-mode and reference requirements.
What LINEGLASS cannot measure
Ordinary USB serial adapters provide decoded bytes, not analog voltage waveforms or wire-edge timestamps. Host arrival timing is influenced by adapter buffering, USB scheduling, the operating system, and browser execution. Logic-analyzer-grade or oscilloscope-grade evidence requires appropriate hardware.
Embedded changelog
v1.0.0Initial complete release: Web Serial, dual ports, capture, framing, decoders, unknown-protocol analysis, visualization, transmit safety, sessions, comparison, and evidence exports.