[ CABLE / ADAPTER RECORD // EIA/TIA-485 2-WIRE HALF-DUPLEX ]
USB-to-RS-485 Half-Duplex Isolated Adapter
USB-to-differential A/B pair plus optional reference/shield; transceiver direction control may be automatic.
CLASSIFICATION: Serial and converter cables. Identify protocol, direction, pinout and exact cable revision before connection.
Interface and capability
| Standard / protocol | EIA/TIA-485 2-wire half-duplex. Connector appearance alone does not establish compatibility. |
|---|---|
| Endpoint / pinout | USB-to-differential A/B pair plus optional reference/shield; transceiver direction control may be automatic. |
| Capability / limits | Classic RS-485 trade-off reaches 10 Mbit/s short-run or 100 kbit/s at up to 1200 m under suitable design; actual adapter/topology sets limit. |
| Certification / length | Standards define interface requirements, not every assembly’s performance. Certification, mode, current/power rating, direction and maximum length belong to the exact product/revision and complete channel; verify its manufacturer specification. Do not infer certification from connector shape or marketing terminology. |
Compatibility & handling
- A/B labels vary; terminate at bus ends only, add bias as required. Verify exact isolation rating and polarity from adapter datasheet.
- Inspect connector keying, latch, contact condition, shielding, jacket and model/revision marking. Stop if contacts are bent, loose, scorched, corroded or mismatched.
- Route without tension or sharp bends; follow product bend-radius, strain-relief, current and environmental limits. Test at the intended protocol and mode—physical fit is not a compatibility test.
Sources & further reading
- TIA-485 StandardsPrimary standards-body or manufacturer reference for EIA/TIA-485 2-wire half-duplex; confirm exact cable assembly, certification and revision.