This is a placeholder topic for “Rail-mount SX1262 LoRa Data Transfer unit (Outputs RS232/RS485/RS422)” comments.
SX1262-LoRa-DTU is a wireless data transfer unit with RS232, RS485 and RS422 interfaces based on the SX1262 module
Read moreMy units arrived with firmware version 1.2, which has a problem with the RS232 mode. If you need to use RS232 mode (particularly on the receiver end), definitely update to fw v1.3 as it resolves this issue. Unfortunately to do the firmware update you need an RS422/RS485 device/adapter though.
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Hi Taylor,
Sorry to hear about that one, reading the product’s wiki there seem to be hiccups with each version. As such I have updated the store page to include a recommendation for a USB to RS485 converter.
Firmware update stops after a few seconds but at varying times on successive attempts to load, having restarted with a new power-on each time. What to try next please?
Hi Graeme,
Welcome to the forum! I’m assuming that you are following the steps outlined in the products Wiki for the upgrade. In the FAQs there is test firmware that you could also try uploading.
Also where did you get the latest updated firmware?
Hello Jack,
Yes I am following the steps to put the DTU into firmware load mode and using a RS485 USB adapter.
The 1.3 firmware was downloaded from the specified location.
The load can stop anywhere between 2 and 28 seconds so far.
I haven’t touched my 2nd DTU which receives RS232 once the key has been pressed, but I won’t try to update that one’s firmware until the first is done.
Port speed 9600 baud, 8N1 and using the Win10 default 4096 tx & rx USB buffer sizes and latency 16ms.
The RS485/USB adapter is only a 2-wire version which means that there is no ground connection between the laptop and the DTU. I’ll try connecting the grounds then try again.
Got further to 34 seconds but obviously not the cause.
Hmm, I was loading 1.3 but 1.3a has appeared since I downloaded 2 weeks ago. However the download still stopped early, this time after 2 seconds.
Can you please send an image of how you have everything wired up?
Sorry, 12V via the DC plug.
My earlier attempt at providing a ground link didn’t, so trying again.
The 3rd or 4th attempt got all the way though to 100% with the laptop’s power led unplugged.
I suspect that a 3-wire adapter would have been a better choice seing that RS485 needs a common ground.
Hi Graeme
Just butting in here.
Why does RS485 need a common ground. It is a balanced line system. The only ground required is for power connections and that is only required if you are running power along with data. Otherwise each drop can be individually powered.
Cheers Bob
EDIT
If you are using screened cable for the balanced data you would need to ground the screen AT ONE END ONLY. Usually at the “receiver” end (professional audio balanced line protocol).
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Thanks for your input Robert.
After hitting my first day’s post limit yesterday, I have since concluded that the failure to upload the firmware has nothing to do with the connection between the RS485 adapter and the SX1262. Instead, either the SX1262 has an issue possibly with its RS485 interface or the adapter is corrupting the data. However as I successfully updated settings in the other DTU a couple of times using Realterm, the adapter may be OK but possibly only OK for low data volumes. Having found the other DTU was already at version 1.3, I assume that the first one would have also been at version 1.3 and therefore did not need to be updated. Unfortunately I assumed from reading other comments that they would need to be updated to power-up in RS232 mode.
As the firmware reload reached 100% several times yet the DTU would not start-up in normal mode (no tx/rx flash after 3 seconds and no LED flash from a short key press to change protocols) on any occasion, the implication is that the DTU is faulty.
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Hi Graeme,
It sounds like a hardware issue. Please shoot us an email and we’ll see what we can do.
I am unable to enter AT Command mode in SX1262-HF-DTU-LoRa module of Waveshare. Have connected the LoRa - serial Port DB9 to Laptop - using SSCOM software or Tera Terminal. Please help. Using these LoRa devices (8nos) in a wireless mesh network on a rooftop for operating pumps ON/OFF operation through a PLC. Have updated Firmware through RS485 port in all the devices.
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Hey @Satish285648, welcome to the forums!
Would you be able to tell us more about this problem?
Do you receive any meaningful error when you attempt to enter AT Command mode?
Would you be able to let us know how far you get through the process before things start going wrong as you follow the wiki?
