Can't get any example to work on Lilygo TS-S3 with sx1280PA chip

[Nikita-Kononov]

I have 2 Lilygo T3-S3 2.4GHz modules for a wireless telemetry project. I cant get any of the examples to work however. Both modules function fine as ESP32 boards (can run different sensors for example) but i cant get them to communicate with each other. Using the Lilygo examples both modules initialize ok, the receiver starts listening ok but after the transmitter sends the first packet i get no confirmation in serial of it being sent successfully. I also tried StuartProjects SX12XX library with the same results. The transmitter tries to send the packet but it never does. The strange thing is that no error codes ever get triggered. I modified the code to print the status to serial and it shows 0 every time. No timeout is triggered either. Both sender and receiver are able to set the frequency correctly as well and all settings are the same for both modules. I tried switching the modules around but achieved the same result. I'm new to this and I feel like I'm making a stupid mistake somewhere but I can't find it and need help.

Sketch that is causing the module fail

As the code is too long to post here: this is the code that i used from lilygo's library. it uses the RadioLib library. The only modifications I made to the code is: uncomment my board type in the utilities.h file and changed the pin numbers according to the schematic I listed below.
https://github.com/Xinyuan-LilyGO/LilyGo-LoRa-Series/tree/master/examples/RadioLibExamples/Transmit_Interrupt

These are the StuartProjects examples that i used:
https://github.com/StuartsProjects/SX12XX-LoRa/tree/master/examples/SX128x_examples/ESP32
Only modification made was the pin numbers in the settings.h file according to the schematic below.

Hardware setup
the schematic from liligo that i used for the pins:

this is the serial output for the transmitter:

this is the serial output for the receiver:

Output using the StuartProjects library:
Similar result as using RadioLib. As a confirmation of the packet being sent successfully, packet info should be displayed after the * which is not happening as well.

SPI Debug mode output

RLB_SPI: CMDW 80
RLB_SPI: SI 0
RLB_SPI: SO FF FF
RLB_SPI: CMDW 80
RLB_SPI: SI 0
RLB_SPI: SO FF 43
RLB_SPI: CMDW 80
RLB_SPI: SI 0
RLB_SPI: SO 45 43
RLB_SPI: CMDW 8F
RLB_SPI: SI 0 0
RLB_SPI: SO 45 43 43
RLB_SPI: CMDW 8A
RLB_SPI: SI 1
RLB_SPI: SO 45 43
RLB_SPI: CMDW 88
RLB_SPI: SI 60
RLB_SPI: SO 45 43
RLB_SPI: CMDW 96
RLB_SPI: SI 1
RLB_SPI: SO 45 43
RLB_SPI: CMDW 86
RLB_SPI: SI B8 9D 89
RLB_SPI: SO 45 43 43 43
RLB_SPI: CMDR 3
RLB_SPI: SI 0 0
RLB_SPI: SO 45 47 1
RLB_SPI: CMDW 8B
RLB_SPI: SI 90 18 3
RLB_SPI: SO 45 43 43 43
RLB_SPI: CMDR 3
RLB_SPI: SI 0 0
RLB_SPI: SO 45 47 1
RLB_SPI: CMDW 8B
RLB_SPI: SI 90 18 3
RLB_SPI: SO 45 43 43 43
RLB_SPI: CMDW 18 9 25
RLB_SPI: SI 32
RLB_SPI: SO 45 47 47 47
RLB_SPI: CMDR 3
RLB_SPI: SI 0 0
RLB_SPI: SO 45 47 1
RLB_SPI: CMDW 8B
RLB_SPI: SI 90 18 3
RLB_SPI: SO 45 43 43 43
RLB_SPI: CMDR 3
RLB_SPI: SI 0 0
RLB_SPI: SO 45 47 1
RLB_SPI: CMDW 18 9 44
RLB_SPI: SI 14 24
RLB_SPI: SO 45 47 47 47 47
RLB_SPI: CMDR 3
RLB_SPI: SI 0 0
RLB_SPI: SO 45 47 1
RLB_SPI: CMDW 8C
RLB_SPI: SI 16 0 FF 20 40 0 0
RLB_SPI: SO 45 43 43 43 43 43 43 43
RLB_SPI: CMDW 8E
RLB_SPI: SI 1C 80
RLB_SPI: SO 45 43 43
Radio : +
PSRAM : +
Display : +
Sd Card : -
Radio Initializing ... success!
RLB_SPI: CMDW 86
RLB_SPI: SI BE CE C4
RLB_SPI: SO 45 43 43 43
RLB_SPI: CMDR 3
RLB_SPI: SI 0 0
RLB_SPI: SO 45 47 1
RLB_SPI: CMDW 8B
RLB_SPI: SI 90 34 3
RLB_SPI: SO 45 43 43 43
RLB_SPI: CMDR 3
RLB_SPI: SI 0 0
RLB_SPI: SO 45 47 1
RLB_SPI: CMDW 8B
RLB_SPI: SI C0 34 3
RLB_SPI: SO 45 43 43 43
RLB_SPI: CMDW 18 9 25
RLB_SPI: SI 32
RLB_SPI: SO 45 47 47 47
RLB_SPI: CMDR 3
RLB_SPI: SI 0 0
RLB_SPI: SO 45 47 1
RLB_SPI: CMDW 8B
RLB_SPI: SI C0 34 2
RLB_SPI: SO 45 43 43 43
RLB_SPI: CMDR 3
RLB_SPI: SI 0 0
RLB_SPI: SO 45 47 1
RLB_SPI: CMDW 18 9 44
RLB_SPI: SI A4 B4
RLB_SPI: SO 45 47 47 47 47
RLB_SPI: CMDW 8E
RLB_SPI: SI 15 80
RLB_SPI: SO 45 43 43
RLB_SPI: CMDR 3
RLB_SPI: SI 0 0
RLB_SPI: SO 45 47 1
RLB_SPI: CMDW 8C
RLB_SPI: SI 18 0 FF 20 40 0 0
RLB_SPI: SO 45 43 43 43 43 43 43 43
RLB_SPI: CMDR 3
RLB_SPI: SI 0 0
RLB_SPI: SO 45 47 1
RLB_SPI: CMDW 8C
RLB_SPI: SI 18 0 FF 0 40 0 0
RLB_SPI: SO 45 43 43 43 43 43 43 43
Radio Sending first packet ... RLB_SPI: CMDR 3
RLB_SPI: SI 0 0
RLB_SPI: SO 45 47 1
RLB_SPI: CMDW 8C
RLB_SPI: SI 18 0 1 0 40 0 0
RLB_SPI: SO 45 43 43 43 43 43 43 43
RLB_SPI: CMDW 8E
RLB_SPI: SI 15 80
RLB_SPI: SO 45 43 43
RLB_SPI: CMDW 8F
RLB_SPI: SI 0 0
RLB_SPI: SO 45 43 43
RLB_SPI: CMDW 1A 0
RLB_SPI: SI 30
RLB_SPI: SO 45 47 47
RLB_SPI: CMDW 8D
RLB_SPI: SI 40 1 0 1 0 0 0 0
RLB_SPI: SO 45 43 43 43 43 43 43 43 43
RLB_SPI: CMDW 97
RLB_SPI: SI FF FF
RLB_SPI: SO 45 43 43
RLB_SPI: CMDW 83
RLB_SPI: SI 0 0 0
RLB_SPI: SO 45 43 43 43

• MCU: ESP32S3 (Lilygo T3-S3)
• core: https://espressif.github.io/arduino-esp32/package_esp32_index.json
• Wireless module type: SX1280PA
• Arduino IDE version: 2.3.4
• Library version: 7.1.2

[jgromes]

As the code is too long to post here

I would suggest to start with minimizing the sketch.

In any case, what you are describing seems to me that the microcontroller halts or crashes when it tries to transmit. The last command I can see in the debug output is RADIOLIB_SX128X_CMD_SET_TX. That's also probably why the same issue appears in multiple libraries. Typically the cause for this is inadequate power supply or some hardware issue, as documented in our Troubleshooting guide.

[Nikita-Kononov]

I'm using the onboard USB-C to power both boards from my laptop. Could that be the issue? I will have access to a proper linear power supply in the next few days and I will try to power them from there.

The code is too long because it's a universal code used for multiple boards that they produce. It has a bunch of if and elseif statements depending on what board is uncommented in the utilities.h file. It's a bit of a pain to read through so i decided to not include it. But the result is the same where it seems to get stuck while sending. Could you elaborate on what the CMD_SET_TX command does?

[jgromes]

The code is too long because it's a universal code used for multiple boards that they produce.

I understand that, but because of this, neither of us understands this code. So I would recommend to use plain RadioLib examples, and learn with those.

Could you elaborate on what the CMD_SET_TX command does?

It initiates the transmission, at which point the power consumption of the SX1280 will be the highest. So if there is a power issue, this is exactly where the MCU would get stuck, or reset.

There is a rather prominent warning on the Lilygo site that output power more than 3 dBm will damage the PA. RadioLib configures 10 dBm by default (if you do not set any arguments to radio.begin()), so you should be careful not to transmit with more than the 3 dBm output, and with a proper antenna connected, of course.

Also, since the same issue manifests in a different library, it seems very unlikely it is due to a software problem in RadioLib, so I will convert this into a discussion.

[Nikita-Kononov]

I have connected both modules to a linear power supply this morning and let them draw as much power as they needed. Unfortunately the result remains the same. I am aware of the transmit power limit of the PA chip and I have been very careful with ensuring that the codes I ran had the correct power setting. I'm assuming this is a hardware issue?