WM1302 on RPI --- TTN showing disconnected questions

Gateways Raspberry Pi Gateways
1

Good afternoon.
I used WM1302 wiki to connect my gateway to the TTN. My gateway is showing disconnected and has been. My RPI console shows the following. Notice GPS listing…It is a bright sunny day here, no clouds, Pixel 6a phone has no issue with GPS and I do have an open area where I am located (ie open sky from trees). Can someone share some insight?

  1. I live in a rural area and am not sure if GPS is not getting found OR if I don’t have something configured correctly for the GPS. Can someone describe how to verify if I have everything set up correctly for GPS? I used the above wiki in the Interface Options section #4 and it looks correct.

  2. If I cannot get GPS signal will TTN show disconnected? Is there a way to over-ride this?

  3. My original beacon frequency in global_conf.json.sx1250.US915 was 869525000 which seemed odd given the board is a US spi 915MHz board so I changed this to 915000000…Is this a problem?

src/jitqueue.c:440:jit_print_queue(): INFO: [jit] queue is empty
### [GPS] ###
# Valid time reference (age: 0 sec)
# no valid GPS coordinates available yet
### Concentrator temperature: 42 C ###
##### END #####

JSON up: {"stat":{"time":"2023-05-30 21:05:29 GMT","rxnb":0,"rxok":0,"rxfw":0,"ackr":100.0,"dwnb":0,"txnb":0,"temp":42.2}}
INFO: [up] PUSH_ACK received in 82 ms
INFO: [down] PULL_ACK received in 79 ms
INFO: [down] PULL_ACK received in 90 ms
INFO: [down] PULL_ACK received in 88 ms

##### 2023-05-30 21:05:59 GMT #####
### [UPSTREAM] ###
# RF packets received by concentrator: 0
# CRC_OK: 0.00%, CRC_FAIL: 0.00%, NO_CRC: 0.00%
# RF packets forwarded: 0 (0 bytes)
# PUSH_DATA datagrams sent: 1 (125 bytes)
# PUSH_DATA acknowledged: 100.00%
### [DOWNSTREAM] ###
# PULL_DATA sent: 3 (100.00% acknowledged)
# PULL_RESP(onse) datagrams received: 0 (0 bytes)
# RF packets sent to concentrator: 0 (0 bytes)
# TX errors: 0
### SX1302 Status ###
# SX1302 counter (INST): 1200830071
# SX1302 counter (PPS):  1200060446
# BEACON queued: 0
# BEACON sent so far: 0
# BEACON rejected: 0
### [JIT] ###
src/jitqueue.c:440:jit_print_queue(): INFO: [jit] queue is empty
#--------
src/jitqueue.c:440:jit_print_queue(): INFO: [jit] queue is empty
### [GPS] ###
# Valid time reference (age: 0 sec)
# no valid GPS coordinates available yet
### Concentrator temperature: 42 C ###
##### END #####

JSON up: {"stat":{"time":"2023-05-30 21:05:59 GMT","rxnb":0,"rxok":0,"rxfw":0,"ackr":100.0,"dwnb":0,"txnb":0,"temp":42.2}}
INFO: [up] PUSH_ACK received in 85 ms
INFO: [down] PULL_ACK received in 80 ms
INFO: [down] PULL_ACK received in 86 ms

This is an addendum to the post
I used the command cat -n /dev/ttyS0 | more and I was able to see legitimate GPS data…
For instance the GGA and GLL messages contained my location data. So why am I getting the #no valid GPS coordinates available yet?

Thank you

2

GPS is Global Positioning System - transmitted from space from about 30Km out, so hard to omit areas and a bit self-defeating if it did.

If you search the forum, you’ll find plenty of other people with GPS issues, of which 99% are irrelevant, as is the GPS hardware.

Only in terms of the concept that the configuration file can automagically determine its location &/or which frequency the board should run at based on its and the boards co-existence / proximity. The software general comes with a starter config but it’s expected that you download the config file from the TTN gateway page once you’ve registered it to update your config.

The very short log you’ve provided doesn’t show any uplinks - do you have device? The gateway console should show the heartbeat messages approximately every 30 seconds.

3

Hello Descartes…
To answer your question:

I have a LoRa-E5 development board as an end device. I cannot seem to get it to join the network. I have verified the EUI on TTN matches my end device. I have copied and pasted the APPKEY, NWKSKEY and APPSKEY from TTN and used the AT+ commands on the device to set these. I have also set the US915 in an AT+ command. I have tried joining the gateway by trying both ABP and OTAA but both times the response from the device was Join Failed…

I also have verified the gateway EUI matches TTN.

I have attached the “global_conf.json.sx1250.US915” that I am using on the gateway
global_conf.json.sx1250.pdf (13.5 KB)

I hope this helps and you can spot something as I am out of ideas of what direction to go at this point…

Thank you for the assistance.

4

The normal file name is global_conf.json so I wonder if your logs show it being read?

But the quick win answer is if anything appears in the activity for the gateway?

PS, devices join the network, gateways are translators of airborne electromagnetic radiation to UDP packets, they don’t think beyond looking for a valid checksum.

5

So…
Absolutely not sure what happened BUT the good news is I am seeing the gateway on TTN!!

btw…for reference only…I tried downloading the global_conf on TTN but when I tried to run it at this end the terminal spit back at me saying there was no JSON object for the SX1302.

In short I don’t know what happened but thank you for your help…If you did something up on the network to get it working I also thank you for that