Difference between revisions of "LGT-92"

From RevSpace
Jump to navigation Jump to search
(TTN mapper configuration)
(What)
Line 12: Line 12:
 
The plan is to investigate if the firmware can be improved, e.g.:
 
The plan is to investigate if the firmware can be improved, e.g.:
 
* fix minor existing bugs
 
* fix minor existing bugs
** see the Issues page at github
+
** see the [https://github.com/dragino/LGT-92_-LoRa_GPS_Tracker/issues Issues page] on github
 
* add Cayenne encoding
 
* add Cayenne encoding
 
* collect information on how to interface with it (over the "USB" port)
 
* collect information on how to interface with it (over the "USB" port)

Revision as of 17:14, 23 November 2020

Project LGT-92
Lgt92.jpg
Improving LGT-92 LoRaWAN tracker software
Status Initializing
Contact bertrik
Last Update 2020-11-23

What

This page is about the Dragino LGT-92, a GPS-enabled LoRaWAN tracker node.

The plan is to investigate if the firmware can be improved, e.g.:

  • fix minor existing bugs
  • add Cayenne encoding
  • collect information on how to interface with it (over the "USB" port)
  • perhaps write a replacement firmware, that can be easily compiled with platformio

Hardware

As far as I understand:

  • STM32L151 microcontroller, could also be STM32L072 I can't get this really clear
  • GPS
  • accelerometer, MPU9250?
  • button, 3 LEDs (R, G, B)
  • 1000 mAh battery + charging circuit

Information provided by Dragino: https://github.com/dragino/Lora/tree/master/LGT-92

Software

Dragino binary firmware downloads: https://www.dragino.com/downloads/downloads/LGT_92/firmware/

My fork of the Dragino firmware: https://github.com/bertrik/LGT-92_-LoRa_GPS_Tracker

Work in progress for an Arduino firmware: https://github.com/bertrik/lgt92

Flashing

When holding the reset pin (e.g. push a dupont-pin in the hole next to the USB connector), you can communicate over SWCLK/SWDIO debug pins.

ST-Link pin connections (from: https://github.com/dragino/LGT-92_-LoRa_GPS_Tracker/issues/10):

 ST-LINK v2 5.0v  <--> Dupont red pin
 ST-LINK v2 GND   <--> Dupont black pin
 ST-LINK v2 SWCLK <--> Dupont green pin
 ST-LINK v2 SWDIO <--> Dupont white pin

For example:

 openocd -f /usr/share/openocd/scripts/interface/stlink.cfg -f /usr/share/openocd/scripts/target/stm32l0.cfg

or

 openocd -s /usr/share/openocd/scripts -f interface/stlink.cfg -f target/stm32l0.cfg

To program a HEX file:

 openocd -s /usr/share/openocd/scripts -f interface/stlink.cfg -f target/stm32l0.cfg -c init -c "program LGT92-EU868-v1.6.2.hex verify reset exit"

This takes only a few seconds.

TTN mapper configuration

Run these commands to set it up with ABP keys, ADR off, uplink at SF7 every 15 seconds:

 AT+NJM=0
 AT+ADR=0
 AT+CFM=0
 AT+DR=5
 AT+LON=1
 AT+MD=0
 AT+DADDR=26 01 1A 30
 AT+NWKSKEY=FB 09 6B 85 86 AF 47 12 E8 AE 67 CB 7F A9 CB 51
 AT+APPSKEY=CB 9B 8F F5 E6 2C 8E 87 9E 0B 6B 1F 4B 69 14 FA
 AT+TDC=15000
 AT+NMEA886=2
 AT+PORT=1
 AT+FTIME=0
 AT+PDOP=10.0