TTGO T-Beam topic

Did you also check that the code does a LMIC_selectSubBand(1); ? There have also been reports of some of the LMIC variants not respecting this but last time I used it I think it was fine… YMMV.

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I’ve changed the LMIC libiary to use v3.1.0 of https://github.com/mcci-catena/arduino-lmic as it has mentioned explicit support for au915, so my lmic_project_config.h now looks like this

// project-specific definitions
//#define CFG_eu868 1
//#define CFG_us915 1
#define CFG_au915 1
//#define CFG_as923 1
// #define LMIC_COUNTRY_CODE LMIC_COUNTRY_CODE_JP /* for as923-JP */
//#define CFG_kr920 1
//#define CFG_in866 1
#define CFG_sx1276_radio 1
//#define LMIC_USE_INTERRUPTS

The ttn-abp.ino example has been updated so, I started with a new example file and added my NWKSKEY, APPSKEY and DEVADDR and change the pin mapping as per the above. Compiles OK, and serial monitor shows the below EV-TXSTART and packet queued. (note: I’m not in range of a gateway). The message only appeared once.
image

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That picture does not identify the version of your board.
It could be V0.5, V0.6, V0.7 or even another 0.x version.

There should be a version number with date somewhere on the PCB similar to:

T22_V05
20180608

The T22 indicates T-Beam, the V05 indicates version 0.5.

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Thanks. Yes I found its a

T22_V07
20180711

Based on the above, are my pin mappings correct?

image

Another unsuccessful wardrive today, TTN console still shows ‘unseen’

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Continuing the discussion from TTGO T-Beam:

Hi,

I got my TTGO beam TTN tracker working - kind of. On a bright day it gets a GPS fix for a few hours and dies afterwards. On a rainy day, no way.

DeuxVis suggested replacing the GPS antenna. Anyone experience with this issue? What antenna should I try?

Geert

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I have had a really huge improvement with those compared to the T-Beam original :

I’m linking for the models, I’m not endorsing those particular sellers you might find better deals at others.

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Hello
From Lilygo shop on ali, I see there are boards in version V1.0 and V1.1, both with AXP192.
Do you now the differences between those?
Did you test deep-sleep on V1.1 and get good results?
Thanks

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Hi,
So, LilyGO have a new T-Beam version 1.1, but detailed information appears lacking (again).

My experience with LilyGO is that they are very poor at providing and updating documentation. I also can’t remember having ever seen documentation that describes what’s new and other changes for new releases of their products. So we probably will have to rely on experiences from users of this board for more information.

LilyGO shows below pinout of the T-Beam v1.1 on the product page on their AliExpress shop but information about v1.1 (and even older versions) is not available on their T-Beam GitHub repository (yet).

T-Beam v1.1 pinout diagram:

TTGO T-Beam v1.1 Pinout Diagram

To see full image size: Right-click image and select ‘open image in new tab’.


If someone has more information about the new T-Beam v1.1 then please share in this topic.

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I compared the descriptions of v1.0 and v1.1. What I found in the v1.1 description which is not in the v1.0 one is the following:
There are 4 LEDs show the battery status in real time
Add reverse battery protection module

As I don’t have my T-Beam yet, does the v1.0 have 4 LEDs for battery indication and a battery protection module?

I ordered a v1.0 a few days ago, I thought that this is the newest version. Nevertheless, I hope that the differences are not that big. But at the moment, the v1.1 cost a little bit more than the v1.0. I ordered my v1.0 with an OLED screen for around 23$ (with shipping). I find the v1.1 one without an OLED screen for around 27$ (with shipping).

2 Likes

Lewis He from LilyGO company has recently published TTGO T-Beam dev. board schematic files for:

  1. V0.7 - 2018 model
  2. V1.0 - 2019 model
  3. V1.1 - most recent for now
4 Likes

So LilyGO have a new GitHub account.

New: https://github.com/Xinyuan-LilyGO
Old: https://github.com/LilyGO

Hopefully they will come with written documentation that also describes what’s new and differences with different/previous versions of same products.
(Until recently it was mostly ‘search the differences’ left up to the customer.)

v1.0 (luckily) does not have a 4-LED battery level indicator.

2 Likes

kizniche / ttgo-tbeam-ttn-tracker

Hey guys. I’m a little late to the party but im having some issues with kizniche’s tracker sketch. I’ve been reading the issue requests on his Github and none of them are really helping me.
The problem I’m having is that I only get the activation message in TTN Console -> data, so im wondering what’s faulty about my setup.
I’ve used the right credentials for OTAA, set up my band in mcci project config and everything else thats provided in his readme.
Also, my end node is trying to activate itself over and over again with no uplink coming through.
This is the output from my activation tab:

{
“time”: “2020-06-07T13:35:55.731483096Z”,
“frequency”: 868.5,
“modulation”: “LORA”,
“data_rate”: “SF8BW125”,
“coding_rate”: “4/5”,
“gateways”: [
{
“gtw_id”: “eui-b827ebfffe34bb20”,
“timestamp”: 3666486788,
“time”: “2020-06-07T13:35:55.711068Z”,
“channel”: 2,
“rssi”: -118,
“snr”: -3.5
},
{
“gtw_id”: “eui-b827ebfffe6b4594”,
“timestamp”: 787828300,
“time”: “2020-06-07T13:35:55.717715Z”,
“channel”: 2,
“rssi”: -114,
“snr”: 0.8
}
]
}

Anyone over here able to identify my problem?
I’m using the T22_v1.0 revision of the board.

2 Likes

Hi folks,

is there any other place to post an issue regarding a specific use case with Tbeam ?
This is a beginner question :slight_smile:

is it possible to send a lora payload from a T-Beam and receive it from a LoRa32 SX1276 OLED (v2) ? I if follow those two tutorials:
https://randomnerdtutorials.com/ttgo-lora32-sx1276-arduino-ide/ or https://randomnerdtutorials.com/esp32-lora-rfm95-transceiver-arduino-ide/, i can send and receive without problem from two LoRa32 devices.

But if i let the LoRa32 receiver ON and tries to send from a T-Beam T22V1.0, nothing seems to happen.

T-beam code: (some gps related vars are set but i removed gps code for clarity. GPS does work fine.)

What am i doing wrong ?

(if i am not in the good place for that kind of beginner issue, please tell me and i’ll try to find a more suitable place for this…)

#include <TinyGPS++.h>
#include <axp20x.h>
#include <SPI.h>
#include <LoRa.h>

#define SCK     5    // GPIO5  -- SX1278's SCK
#define MISO    19   // GPIO19 -- SX1278's MISnO
#define MOSI    27   // GPIO27 -- SX1278's MOSI
#define SS      18   // GPIO18 -- SX1278's CS
#define RST     23   // GPIO14 -- SX1278's RESET
#define DI0     26   // GPIO26 -- SX1278's IRQ(Interrupt Request)
#define BAND  868E6

TinyGPSPlus gps;
HardwareSerial GPS(1);
AXP20X_Class axp;

void setup()
{
  Serial.begin(115200);
  Wire.begin(21, 22);
  if (!axp.begin(Wire, AXP192_SLAVE_ADDRESS)) {
    Serial.println("AXP192 Begin PASS");
  } else {
    Serial.println("AXP192 Begin FAIL");
  }
  axp.setPowerOutPut(AXP192_LDO2, AXP202_ON); //lora
  axp.setPowerOutPut(AXP192_LDO3, AXP202_ON); //gps
  axp.setPowerOutPut(AXP192_DCDC2, AXP202_ON); 
  axp.setPowerOutPut(AXP192_EXTEN, AXP202_ON);
  axp.setPowerOutPut(AXP192_DCDC1, AXP202_ON); //oled
  GPS.begin(9600, SERIAL_8N1, 34, 12);   //17-TX 18-RX

  SPI.begin(SCK,MISO,MOSI,SS);
  LoRa.setPins(SS,RST,DI0);
  if (!LoRa.begin(BAND)) {
    Serial.println("Starting LoRa failed!");
    while (1);
  }else{
    Serial.println("Starting LoRa succeed!");
  }
  
  axp.setChgLEDMode(AXP20X_LED_BLINK_1HZ);

}

void loop()
{
  LoRa.beginPacket();
  LoRa.print("Hello");  
  LoRa.endPacket();
  Serial.println("sent..");

  delay(1000);
}

Thanks :slight_smile:

1 Like

Hi @xefiji,

Your example is about LoRa point-to-point connections while this forum is about The Things Network (TTN) and LoRaWAN. With LoRaWAN nodes send messages to gateways which forward the messages to a central TTN backend server where they are picked up by user applications.
LoRaWAN does not support point-to-point connections and latter are not supported on the forum.

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Thank you @bluejedi ok i’ll try somewhere more appropriate for my use case (SO or Github) .

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Hi guys,

Does anyone made a platformio port of https://github.com/kizniche/ttgo-tbeam-ttn-tracker ? Or does anyone know where to find it ?

I’m trying it myself but I’m getting stucked in converting issues.
And why should I re-invent it when somebody else already has :wink:

Thanks

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There are not so many changes in schematics / parts of the most recent T-Beam v1.1 revision for paying attention to.
However, the PCB layout has been altered a little bit. Which makes older 3D enclosure for v1.0 to be no longer appropriate for v1.1

This is an illustration of all the ‘exterior’ updates:

More details are available at this Thingiverse page .

2 Likes

I have a question regarding the frame counter check. Do I have to reset the counter every time I restart the t-beam? I am using hottimucs mapper.
image
Is this the frame counter?

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LilyGO direct AliExpress store has started to process orders on a new variant of the T-Beam board with most recent Semtech SX1262 LoRa radio IC:

  1. T-Beam SX1262 with ublox NEO-6 GPS module: AliExpress 1 2
  2. T-Beam SX1262 with ublox NEO-8 GNSS module: : AliExpress 1 2

It is expected to be Semtech “LoRa Space” friendly in:

  • 433 MHz band variant - to operate with FOSSA Systems satellite(s)
  • 868 MHz band variant - to operate with Lacuna Space satellite(s)

This improved T-Beam is known to work nicely with TTN by means of port of BASICMAC (successor of LMIC) LoRaWAN library for Arduino IDE.

4 Likes

I need help in case of OTAA. It just stays on EV_JOINING. I am using the hottimuc mapper. It works with ABP, though. What could that be? The frame counter looks a bit odd, too. Do you still need to reset frame counter when using OTAA? When I choose SF8 it says “OP_TXRXPEND, not sending”, what does that mean?
IMG_1946
Sorry for the black bar on the top, that’s due to the refresh rate of the display.

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