Revision History
Revision Date
Comment
Firmware
Version
1.00
11/11/21
Swarm M138 Modem Product Manual - Initial Release
1.01
12/01/21 Corrected pinout table
Updated $GN and $GS descriptions
Updated Modem status message structure
Updated date/time format to reflect YYYY-MM-DD
T
HH:MM:SS
1.02
12/07/21 Updated Table 6 to reflect Figure 4
1.10
01/12/22 Updated transmit current measurements
Removed section 3.3
Updated T/R pin notes
Updated $GP command description
Updated M138 Modem images
Updated regulatory information
1.11
01/20/22 Added antenna guidance to Section 6
1.20
02/15/22 Updated power characteristics for all M138 operating modes
Updated RSSI_bkgnd operating range
Updated GPIO1 mode description
GPS Cold/Warm start flowchart and timings
1pps pin removed
$MT L=U command option removed
Updated capacitance and inductance table
2.0.0
Additional Resources:
Please visit our developer tools webpage for quickstart guides and other helpful resources:
https://swarm.space/developertools
© 2022 SWARM TECHNOLOGIES
SWARM M138 MODEM PRODUCT MANUAL · REV 1.20 · FEBRUARY 2022
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