The CalAmp LM Direct protocol is the wire format CalAmp's LMU, MTM, and MXT GPS hardware families use to report data. CalAmp is a US-listed company (NASDAQ: CAMP) headquartered in Irvine, California, with deep penetration into the North American fleet, insurance telematics, and connected-car markets. LM Direct is documented to integrators · Traccar's open-source decoder is the most-cited third-party implementation.
Protocol-at-a-glance
- Transport · UDP (canonical) · TCP variant for some firmware
- Default port ·
5082(Traxelio's ingest port; matches Traccar's calamp decoder default) - Encoding · binary, length-prefixed records, big-endian
- Auth · ESN (electronic serial number, CalAmp's IMEI equivalent) in first packet
- Inbound messages · "User-Defined" message types (0x01-0x09) carry positions, events, accelerometer data, and OBD-II PIDs
- Outbound messages · server can push commands, configuration updates, and over-the-air firmware via the same channel
Why CalAmp hardware dominates North American fleets
- Long-standing US presence · founded 1981, NASDAQ-listed, ~3,000 employees · the kind of supplier stability US enterprise fleets demand
- Insurance telematics anchor · CalAmp is the OEM behind several major US insurance UBI (usage-based insurance) programs · Allstate Drivewise and others
- MXT-150 / LMU-3640 / LMU-4230 · the workhorse models for North American fleet (heavy-duty trucks, government / municipal, rental)
- UDP-first design · LM Direct is UDP-canonical, which suits the spotty cellular coverage patterns of US interstate freight better than TCP's connection-state overhead
The trade-off vs European pros (Teltonika, Ruptela): CalAmp's per-unit cost is higher, sold mostly through CalAmp's direct sales force and integrator partners rather than through reseller channels.
Configuring a CalAmp device for Traxelio
Two paths · PEG Scripting (CalAmp's Programmable Event Generator) or CalAmp Configuration Tool (Windows desktop):
Configuration Tool path:
- Connect the device via USB serial
- Open CalAmp Configuration Tool
- Set the Inbound URL to Traxelio's UDP endpoint, port
5082 - Save and reboot
- First position usually arrives within a minute
PEG Scripting path (for sophisticated event logic):
CalAmp's PEG (Programmable Event Generator) is a scripting environment that runs on-device · operators write event triggers (geofence, accelerometer threshold, PTO engagement) that fire reports to specific server URLs. Useful for complex fleet behaviour but requires familiarity with the PEG language.
Supported devices in our catalog
24+ devices declare protocol: "calamp" · the headline models: CalAmp LMU-3640, LMU-4230, LMU-2640, MTM-3640, MTM-4230, MXT-150, MXT-110. The MXT line targets asset/trailer tracking (lower power); the LMU line targets vehicle tracking (mid-power); the MTM line targets heavy-vehicle / OBD-II integration.
LM Direct vs MXT vs the CalAmp ecosystem
CalAmp uses several closely-related but distinct wire formats across its product lines:
- LM Direct · the canonical CalAmp protocol · used by LMU, MTM, and most MXT models
- MXT protocol · a separate Traccar slug (
mxt) for some older MXT-150 variants that pre-date the LM Direct unification · functionally similar, slightly different packet shape - Phantom Web Services · CalAmp's web platform · not a wire protocol but the SaaS layer most CalAmp fleets historically sat on
Traxelio's calamp decoder handles LM Direct natively. The legacy mxt slug (14 catalog devices) is handled by Traccar's separate mxt decoder · also supported but historically pinned to the older firmware revisions.