Tonghui TH2822D CLI

A Linux command-line replacement for the TH2822D Windows LCR Software. It controls every SCPI operation documented by the meter and adds script-friendly configuration snapshots, typed readings, continuous JSONL/CSV capture, raw commands, and batch execution.

Tested with:

TH2822D Handheld LCR Meter,VER4.5.2307,SNQ48C240168

Coverage

• All 19 documented SCPI catalog entries, representing every query, setting, action, tolerance value, recording statistic, and measurement fetch
• CP2102 discovery and identity probing; explicit --port selection
• L/C/R/Z/DCR primary parameters and D/Q/THETA/ESR secondary parameters
• 100/120 Hz and 1/10 kHz test frequency, 0.3/0.6/1 V test level, and series/parallel equivalent modes
• Instrument-side tolerance and min/max/average recording
• UTC-stamped JSON, JSONL, CSV, and tab-separated text data acquisition
• Catalog-based get, set, and action, plus raw and batch
• Stable independent invocations without toggling front-panel control

TH2822E's 100 kHz mode is intentionally not exposed by the typed TH2822D configuration command. It remains available through raw when using compatible hardware.

Install

Python 3.10 or newer is required.

git clone https://github.com/LHX369963/th2822d-cli.git
cd th2822d-cli
python3 -m venv .venv
. .venv/bin/activate
python -m pip install -e '.[test]'

The CP210x node is normally owned by root:dialout. Add the user to dialout once if needed, then log out and back in:

sudo usermod -aG dialout "$USER"

Do not run the CLI with sudo.

Use

th2822d list
th2822d info
th2822d config
th2822d read

th2822d configure --primary C --secondary ESR --frequency 100 --voltage 0.3 --equivalent PAL
th2822d monitor --count 20
th2822d monitor --duration 60 --format csv --output capacitor.csv
th2822d monitor --count 100 --format txt --output capacitor.txt

th2822d configure --recording ON
th2822d recording
th2822d configure --recording OFF

th2822d configure --tolerance-range 5 --tolerance ON
th2822d tolerance
th2822d configure --tolerance OFF

Catalog and low-level workflows:

th2822d commands list
th2822d commands list --section recording
th2822d commands show function.primary
th2822d get frequency.test
th2822d set voltage.level 0.6
th2822d action general.trigger
th2822d raw 'FETCh?'
th2822d batch commands.scpi

Output is compact JSON. monitor emits JSONL by default so each line is a complete record suitable for streaming tools. Measurements use SI base units (F, H, ohm, deg); display prefixes never need to be parsed. CSV is the recommended durable capture format and opens directly in spreadsheet software without adding a spreadsheet-specific runtime dependency.

Use --port /dev/ttyUSB0 when more than one compatible adapter is connected. Automatic discovery probes CP2102 adapters with *IDN? and only accepts a TH2822-series identity. The default two-second timeout can be changed with --timeout.

Any SCPI command places the meter in remote mode. Ordinary invocations remain remote on exit; use action general.go-local or the physical RMT key to restore front-panel control. An earlier E10 was initially correlated with *GTL, but the command later passed repeated isolated tests after the transport delay was increased and Linux HUPCL was disabled. Do not use general.local-lock unless locking the physical RMT key is intentional.

In DCR mode the secondary display is implicitly NULL. The CLI does not query FUNCtion:IMPB? while DCR is active because firmware VER4.5.2307 reports E10 for that invalid combination. Other non-applicable DCR configuration fields are returned as JSON null.

Safety

Discharge capacitors before connecting or removing them. Never measure a powered circuit, and do not apply external voltage to the LCR terminals. USB remote control does not change these instrument safety requirements.

Verification

python -m pytest
python tools/live_acceptance.py --port /dev/ttyUSB0

The tracked Codex skill is in skills/th2822d-cli. Protocol details and observed firmware behavior are in docs/protocol.md. Connected results are recorded in docs/validation.md.

The legacy Windows application's extracted resource inventory and workflow mapping are documented in docs/windows-parity.md. The supplied Chinese user manual and series datasheet are retained under docs/official/ with SHA-256 checksums.