TTGO T-Call 1.3 (Lilygo)

11 thoughts on “TTGO T-Call 1.3 (Lilygo)”

1. Hello Stefan, thank you too for the good compilation of information. This has enabled me to switch over excellently from my first ESP8266 prototypes.
   My goal was a GSM/GPS module that sends position data via secure websockets.
   When I realised I couldn't get the combination of PPPoS, WSS and GPS to work with Arduino libraries, I had to switch to the creepy ESP-IDF SDK. There are also plenty of examples for all the individual components there, but you dive into the annals of C programming.
   With a few modifications (correct UART config, correct RX pin, increasing the buffers) everything worked for the first time last night and I had a really nice alcohol-free beer!
   As a SIM card, I use Netzclub's free data cards (200MB for free, then throttled to 64kBit/s, which suits my needs).
   I hope to find the time to strip down my project to a sample with comments and will then post a link here in the forum.
   Markus's VG

   Reply

   1. Hello Markus,
      Thank you for your contribution. I've also „played around“ with the Espressif IDF; you can't get past it. Especially if you want to program the new ESP32-S2, you don't have any other choice. In my opinion, the code in the IDF is exponentially harder to read, but you can expect the most up-to-date changes to be in the IDF. I'm also considering switching to it.
      I think the free data card is great, I've already included it in the post.

      Hello
      Stefan

      Reply

2. Many thanks for the SMS example. I've also bought the following GPS module (GPS Module GPS-NEO-6M-00) and soldered it to the TX and RX connections. However, I'm not managing to receive GPS data from it using TinyGPS++ or many other methods. I'm using TX = 1, RX = 3 in the program code. I've also tried many other pin numbers, but nothing is working. Do you have any ideas?

   “’#include
   #include

   // The TinyGPS++ object
   TinyGPSPlus gps;
   HardwareSerial SerialGPS(1);

   void setup() {
   Serial.begin(115200);
   SerialGPS.begin(4800, SERIAL_8N1, 3, 1);
   }

   void loop() {
   while (SerialGPS.available() > 0) {
   gps.encode(SerialGPS.read());
   if (gps.location.isUpdated()) {
   Serial.println(„Latitude= „);
   Serial.print(gps.location.lat(), 6);
   Serial.print(F(“Longitude= „));
   Serial.println(gps.location.lng(), 6);
   }
   }
   “

   Reply

   1. Hello Tinkerpete,

      I don't have a specific suspicion, perhaps a few pointers. I had tested the neo6 V2 once, the link is here:

      https://www.fambach.net/gy-neo6mv2-gps-modul/

      The connection speed was 9600 baud for me, as far as I can see, and a few other websites on the internet confirm that too, try it with that.

      As far as I'm aware, pins 1 and 3 are already used for UART0 (Serial), which might clash with USB.

      Uart1/Serial1 is probably used for the flash memory

      So, Uart2/Serial2 (GPIO 17 and GPIO 16) remain.

      I couldn't quite work that out from the ESP datasheet, but I think the pins are quite freely configurable.
      Andreas Spies has made a video about that, which I haven't seen yet though: youtu.be/GwShqW39jlE?t=182

      In my example, I didn't explicitly use the hardware Serial, but rather Serial2, assigning pins and a baud rate to it.
      What you can also try is the SoftwareSerial, here any bidirectional IO port should work.

      Hello
      Stefan

      Reply

      1. Thank you for your detailed reply. At the moment, I've desoldered the GPS module again and connected it to an Uno. I had problems there at first too, but now I'm finally getting the output from the GPS module via RX=2 and TX=3! So it's not defective, at least. Now I'm trying a more differentiated output with TinyGPSPlus, which strangely doesn't work with all the examples from the internet. When I have it back on the T-Call, I'll try the GPIO 17 and GPIO 16 you mentioned.

         Reply

         1. Hello,

            Slightly longer addendum from me, GPIO16/17 on the top are marked (NC) for not connected.
            I've now tested my example with pins 32/33 and it works (at 9800 baud).
            I must mention that I have only addressed the Neo6-M module now and no further components.
            Another thing that occurred to me is that some modules are a bit fussy about the supply voltage; you could try setting this to 5V (at least for my module, check the datasheet first).

            Greetings Stefan

            Reply

         2. Hello Tinkerpete,

            Did it work out for you now?

            Reply

            1. Yes, it works for me: http://steinlaus.de/wie-man-mit-aldi-talk-dem-esp32-die-freiheit-gibt/

               Reply

3. Hello Thomas
   Thanks for your contribution. These things are really amazing and at least in the test it worked well. Which SIM cards do you use? I tested it with Aldi and Things Mobile.
   https://www.sim4iot.de/ I found it too.
   Hello
   Stefan

   Reply

   1. I haven't managed to send an SMS with the example code yet.
      I am using a prepaid SIM card from Blau, which is actually installed in a GPS tracker and was temporarily removed for testing purposes.
      I ordered 2 SIM cards from Things Mobile yesterday.
      When the cards come in, we're moving on to round 2 😉
      Best regards
      Thomas

      Reply

4. Thank you very much for your contribution.
   I've also got a few of these chips and thanks to your description, I was able to get started straight away.
   I've only used the small Wemos so far and am entering new territory with the GSM module.
   The tip regarding the SIM card is also promising.
   Thank you

   Reply