Start UART integration with the exact module and its current manual. ERDILRF modules do not share one supply range, connector pinout or serial frame. A UART label alone does not establish the signal voltage, baud rate, distance unit or command set.
Revision note — 5 October 2026: Earlier versions of this article described one common interface across the catalog. Those generalizations have been removed. Use the model-specific checks below before wiring or adapting a parser.
Confirm the electrical interface before connecting
- Identify the exact part. Record the module designation and manual revision. Open the matching datasheet, rather than borrowing a diagram from a similar-looking module.
- Check supply and signal levels separately. LRF50H lists a 9–36 V DC supply; LRF22VB lists 3.0–3.6 V DC. Neither model’s source separately specifies a numerical UART logic level. Do not derive that value from the supply voltage; confirm it before connecting the host.
- Follow the exact connector drawing. Check the viewing direction, pin number and signal name. An undocumented wire color, reserved pin or enable polarity needs confirmation before use.
- Use the model’s timing requirements. Check any documented power sequence, peak current, start-up delay and measurement mode. A delay or current figure from one module is not a catalog-wide rule.
Sources: LRF50H specifications and manual and LRF22VB specifications and manual. If the delivered configuration differs from the document, resolve that difference before applying power.
A matching frame header is not enough
These two source-documented examples share a header and frame length, but use different distance units:
| Exact model | Documented UART output | Distance unit in the example |
|---|---|---|
| LRF50H | 4 bytes, 5C header |
Centimetres |
| LRF22VB | 4 bytes, 5C header |
Millimetres |
This is a comparison of those two models, not a wiring diagram or a complete parser. Do not apply one distance conversion across the catalog or treat every byte sequence beginning with a familiar header as a valid measurement.
Build the parser from the exact protocol
- Confirm baud rate, framing, reply length and the command used to request data.
- Read the documented byte order, distance fields, units and invalid-result indicators.
- Validate the checksum using the scope specified for that message direction. Command and reply rules may differ.
- Handle incomplete frames, failed measurements and stale readings separately. Decide what the host application should do in each case.
LRF1200A1 explicitly notes that the verification content for sending and receiving may differ. SPD1200D03 has conflicting baud-rate statements in its source documents, as well as different transmit and reply checksum scopes. Confirm the delivered SPD1200D03 configuration instead of choosing one listed rate.
Use the available driver with its documented limits
Open Drivers & Integration for the current Python, Arduino and ROS 2 resources, model coverage and known gaps. Select the exact model explicitly and read its limitations before sending a command. An example for one model does not establish compatibility with another.
For a first bench check, agree the electrical connections and protocol settings first. Then compare captured bytes with the exact manual’s examples. No output by itself does not identify whether the cause is wiring, power, configuration, command mode or host parsing; avoid changing several unknown settings at once.
Get help with the exact integration
Send the module designation, manual revision, host board or adapter, intended interface and a short description of the symptom. A short byte trace can help with protocol review; remove private data before sharing it.
Send a technical inquiry or email tommy@erdimail.com. Include any unresolved pin, signal-level or document conflict so it can be checked before wiring.
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