SX1261 with stm32U5

[Nameless]

 Hello, i am working on a project involving Wake-Up Radios (WuR) for underground sensor networks. The system is based on a STM32U5 microcontroller and a SX1261 LoRa transceiver module,

I have a problem with the BUSY pin the transmitter is stuck waiting for the BUSY pin to go low after sending commands. The STM32 reads the BUSY pin as logic high (1) indefinitely, but an external oscilloscope shows the BUSY line is actually low (0). This discrepancy prevents the program from proceeding, as it continuously waits for the BUSY pin to go low. 

The pin is configured as an input without pull-up or pull-down resistors. I've verified the pin number and mapping several times.

In addition to that, I want to confirm that the SX1261 is actually starting transmission when I send a command. Currently, I don’t receive any TX_DONE interrupt, and the transmission seems to silently fail. Is there any known method to verify that TX is starting on the SX1261? Also, is there a way to bypass the BUSY pin check just for debugging, to see whether the transceiver accepts commands even if the BUSY state appears incorrect?

Any help or guidance would be appreciated.

Thanks.

[Andrew Neil]

Welcome to the forum

Please see How to write your question to maximize your chances to find a solution for best results

Note that the SX1261 is a Semtech product - nothing to do with ST - so you need to go to Semtech for specific questions about their product:

https://www.semtech.com/products/wireless-rf/lora-connect/sx1261#talk-with-us-today

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@Nameless wrote:

The STM32 reads the BUSY pin as logic high (1) indefinitely, but an external oscilloscope shows the BUSY line is actually low (0). .

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Are you probing directly at the pin  on the STM32 package?