Big ESP32 + SX127x topic part 2

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Does anyone use Micropython to connect this board to the TTN? I cannot find a library that has those functions.

Hey! I have a Heltec Wifi Lora ESP32 board. When I tried running the ttn-abp code, it is able to send the payload once, and it won’t continue to send after that. In the serial monitor output, it never runs the EV_TXCOMPLETE.

In my config.h file, I have set it to #define CFG_us915 and #define CFG_sx1276_radio. I have set the appropriate network session key and application session key. Is there a wiring issue that I might’ve skipped over? Would it be on the TTN side of not configuring something?

const lmic_pinmap lmic_pins = {
    .nss = 18, 
    .rxtx = LMIC_UNUSED_PIN,
    .rst = 14,
    .dio = {/*dio0*/ 26, /*dio1*/ 33, /*dio2*/ 32}

:drum: :drum: :drum: :drum: :drum: :drum: :drum:


My optional 0.96 OLED front panel is a remix of this Thing .


I found another OLED with 1.3" and has the “strange” pin layout too :wink:
The overall size is high: 33.5mm width: 35.4mm
could you please give me the size of the board? I couldn’t find it. Thanks

My T-Beam’s PCB size is (LxH) : 100x33 mm

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It would be nice if you put the files online on Thingiverse and GitHub, too.

Sure I will, but not today.

Where is the best place to buy the Heltec Wifi LoRa 32?

you find it on some amazon sites, probably fastet way to get one. If you not, you can order it on Aliexpress.

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Cased my TTGO T-Beam, thanks to the creator of the case! Printed by 3d hubs print service.


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Can you say how much 3d hubs charged for the print ?

I paid 17,92€ including shipping (tracked). My order was routed to a print service in norther Germany (Joerg in Schortens).
4 days until delivery.

I see blue light coming from battery status LEDs, so you have one of the very first revisions of the T-Beam, right?
Does the window in the lid match your antenna connector ? I saw this picture before for the board similar to yours:


In the revision (t22_v6 21080705) of the T-Beam’s PCB that I’ve used while doing this enclosure design, antenna connector is in 1 mm off the centerline.

Yes, my TTGO T-Beam is probably an early type. Got it from Liliygo as sample for fitting paxcounter to it. Case matches exactly in all dimensions.

Hi Guys,

This looks like a great topic.

I have one of these little Heltec boards with the OLED display.
Currently it just attempts to send data with the built in test code.

I am not an Arduino person so not that familiar with trying to modify code for this device.

I would like to find a pre built application that I can use to turn this device into a network monitoring/test node for my TTN gateways. I am based in Australia and using AU915 band plan.

Has someone already managed to get some basic LoRaWAN test code working on this device? It would be nice if the display showed some basic network parameters like RSSI, SNR, time, etc.

It would make a useful little test node.

A simple way to set up OTTA registration (maybe via the USB port) would probably be needed.



New TTGO 2.1 v1.6 with preloaded paxcounter software spotted recently on Ali:

I’m running a TTGO with OLED as a single channel gateway. The code I’m using was from

The OLED displays

FYI I’m using another TTGO as the node, using


I’m having an issue with my TTGO setup.
Using one as a sc-gateway, one as a node (see above message).

On the node, if I enable the OLED, the messages are NOT showing up on the ttn console, suggesting the U8 lib or OLED somehow corrupts the data packet.
The OLED display is working, for now I have it displaying ‘Starting Node’ after display.begin(); in setup().
Packets show on the gw OLED, and the gw shows they are received in the Message Statistics.

FYI I’m following the bluejedi’s notes, using as923, and the Heltec_WiFi_LoRa_32 pinmap. Boards are TTGO V1.


Thanks Dave, This will help in the short term.
Ultimately I would like to find a MicroPython version that will run on the TTGO and similar hardware as a LoRaWan client. I have a group of MicroPython enthusiasts who are all interested in developing simple low cost application nodes.