Settings and Configuration

Overview

Miro Cargo is configured with LoRaWAN^® downlinks which are transmitted to port 220. The payload of a configuration downlink corresponds to a so-called AT command. After one or more configuration downlinks are received, a reset command needs to be transmitted to the miro Cargo such that the configuration is stored in non-volatile memory and a reset is triggered. After this reset, the miro Cargo uses the new configuration.

Downlink commands

Overview

The following configuration downlands are available:

Command	Description	Default value	Min value	Max value	Unit
ATZ	Reset the MCU	-	-	-	-
AT+GPSHOLD=<value>	Moving interval (GPS hold time)	120'000 (2 min)	60'000 (1 min)	4'294'967'295 (49.7 days)	ms
AT+GPSCYC=<value>	Steady interval (GPS cycle time )	21'600'000 (6 hours)	60'000 (1 min)	4'294'967'295 (49.7 days)	ms
AT+STACYC=<value>	Status message interval	21'600'000 (6 hours)	600'000 (10 min)	4'294'967'295 (49.7 days)	ms

ATZ

Resets the MCU. If the configuration has been changed, the new configuration is stored in non-volatile memory and applied after the reset.

AT+GPSHOLD

Sets the GPS hold time, also known as a moving interval. The GPS hold time inhibits further GPS fix acquisition for a certain time period. This setting is used when GPS fixes are triggered by the accelerometer. A first accelerometer event will trigger GPS fix acquisition immediately. Further accelerometer events will be ignored until after the hold time interval. However, a flag will be set in this case, so that the next GPS fix acquisition will immediately start right after the hold time interval.

Example

Setting the moving interval to 5 minutes (300 seconds)

AT+GPSHOLD=300000

AT+GPSCYC

Sets the regular GPS fix cycle time, also known as a steady interval. The GPS cycle time is used when GPS fixes are triggered by the timer. The GPS cycle time is the time between two consecutive GPS fix acquisitions. The GPS cycle time is running independently of accelerometer events.

Example

Setting the steady interval to 1 hour (3600 seconds)

AT+GPSCYC=3600000

AT+STACYC

Set the regular status interval. Status messages are enabled by default, all sensors are read out when the regular status interval expires. Please refer to the payload documentation for more information about the generated status message. To save battery life, keep it at a large value.

Example

Setting the status interval to 12 hours (43200 seconds)

AT+GPSCYC=3600000

Downlink responses

For every downlink packet, an uplink packet is scheduled containing the corresponding AT response code. The following response codes are available:

Response code	Hexadecimal	Description
AT_OK	41545F4F4B	Command executed successfully
AT_PARAM_ERROR	41545F504152414D5F4552524F52	Command was outside of the valid range
AT_ERROR	41545F4552524F52	Command execution failed

Downlink command format

The payload of an AT command downlink corresponds to an ASCII encoded AT command with zero-termination. Zero-termination means that 00 needs to be added at the very end of the hexadecimal representation of the AT command. The last line of the following examples corresponds to the payload of the respective downlink.

Example

Changing the moving interval to 3 minutes (180 seconds) send the following command

Representation	Data
ASCII string	AT+GPSHOLD=180000
Hex	41542B475053484F4C443D313830303030
Hex with zero termination:	41542B475053484F4C443D31383030303000

Example

Resetting the device:

Representation	Data
ASCII string	ATZ
Hex	41545A
Hex with zero termination:	41545A00

Important

After changing a configuration parameter via downlink, the miro Cargo needs to be reset such that the configuration is loaded. This is done by sending the downlink command ATZ on port 220.

For every downlink packet, an uplink packet is scheduled containing the corresponding AT response code (usually AT_OK or 41545F4F4B in hexadecimal representation). If both the configuration change and the reset are queued simultaneously on the LoRaWAN^® network server, the configuration is applied the fastest way possible. The reason for this being that the configuration change triggers an uplink message (usually AT_OK) which opens another downlink slot for the reset command to be received immediately.