Multi-Tech MultiConnect mDot MTDOT Series, Руководство разработчика

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APPENDIX A RELEASE NOTE ARCHIVE
MultiConnect
®
mDot
TM
MTDOT Developer Guide for Japan 65
Command Function
AT+CHM New, enables channel mask.
AT+MAC New, injects MAC command.
Maintenance Release 1.0.8-1
Firmware release 1.0.8-1 addresses power consumption in sleep mode. For power draw changes, refer to notes
and measurements in
Power Measurements .
What's New in Firmware Version 1.0
The release includes the following changes:
Separate AT Command Reference Guide document, with expanded details.
Enhanced support of LoRaWAN 1.0 and 1.0.1 specification.
Adaptive Data Rate
Peer to Peer
EU868 Test Mode
Enhanced sleep mode
Preserve session
About Adaptive Data Rate
LoRaWAN provides MAC Commands, LinkADRReq and LinkADRAns to support Adaptive Data Rate (ADR).
ADR allows the network server to change a device’s data rate, Tx power, and repetition settings. If ADR is enabled,
the network server samples the SNR from each packet and computes a possible data rate based on that sample.
The possible data rate for a number of packets is held until the packet threshold is met. Once the threshold is met,
a LinkADRAns MAC command is sent to request that the device change data rate.
For the ADR to judge the SNR correctly, set Tx power to maximum. Greater power savings are achieved through
Highest Power/Highest Data Rate than with Lowest Power/Lowest Data Rate. Each step in spreading
factor/bandwidth (SD/BW) gives about 3 dB increase in link budget.
Once the highest data rate is assigned, the network server looks at adjusting Tx power. If the SNR ratio for the last
several packets is 3 dB above the highest data rate threshold, power is lowered.
Related commands
AT+ADR – Enables adaptive data rate
AT+SDR - Shows the current data rate
Peer to Peer Communication
Peer to Peer mode allows mDots to communicate without a network server. Two mDots can be configured with
identical network addresses and session keys and default to receive mode. In peer to peer mode, both mDots are
in listen mode when not transmitting and, if acknowledgments are enabled, every data packet is acknowledged
immediately.