RF Communication with Nucleo-WL55JC Boards - Seeking Guidance

[Zayoud]

Hello ST experts,

I am a beginner with the STM32WL series and need some support.

So first I started with the STM32F407VG disc1 and I tried to communicate two boards of it using a SI4432 module and I didn't succeed, I tried something else and I bought two Nucleo-32WL55JC1 boards and tried to communicate them and it works as shown in the last post.

It works as a ping pong application -you can find a better description about this application in this link page 44- after that I tried by developing the same code of the ping pong application to communicate a nucleo-32wl55jc1 with nucleo-32wl55jc2 because in the datasheet they don't use the same frequency but it works!

Now I am working on RF communication between nucleo-32wl55jc2 and another RF device like a key car or a key garage with the same developed code of the PING PONG application but still I don't have any answer.

My first question is if the NUCLEO-WL55JC cards are able to read RF signals from these RF devices?
The second one is if the code of the PING PONG application forces me to use only NUCLEO-WL55JC boards or B-WL5M-SUBG1 device?

For example, if I change the RF configuration to match the configuration of the RF device.

And, what is the meaning of the RF range specified in the data sheet of the NUCLEO-WL55JC boards?

Finally, I tried to communicate with the device that has this configuration

Are these variables the only ones used in the RF configuration? if not, I would appreciate it if you could specify the critical variables that I need to identify in order to program the NUCLEO-WL55JC boards for effective communication.

In conclusion, I kindly request a link to an RF training course or a recommendation for a book that could further enhance my understanding of RF communication principles.

Thank you for your time and assistance.

@STTwo-32 
Best regards,
Zayoud

[Andrew Neil]

---

@Zayoud  wrote:

I am a beginner with the STM32WL series 

---

Do you have any experience with any other microcontroller(s) ?
Electronics in general?

@Zayoud

---

 wrote:

My first question is if the NUCLEO-WL55JC cards are able to read RF signals from these RF devices?

---

It's certainly not the type of thing that the WL are really targetting.

To answer that, you're going to need to find the specifications for those "RF devices" - in particular,

• On what frequency they operate
• What modulation they use
• What protocol they use over the link.

---

@Zayoud  wrote:

if the code of the PING PONG application forces me to use only NUCLEO-WL55JC boards or B-WL5M-SUBG1 device?

---

I think ST provides the Ping-Pong example for all of its LoRa-based products - so no, it's not restricted to just WL

However, car & garage door openers tend to be unidirectional - so they certainly won't do a Ping-Pong.

And they don't do LoRa.

---

@Zayoud  wrote:

I kindly request a link to an RF training course or a recommendation for a book that could further enhance my understanding of RF communication principles.

---

"RF communications" is a vast field!

Books will be large & expensive; courses will be long ...

https://www.google.com/search?q=RF+communication+principles+book 

[STTwo-32 · Accepted solution]

Hello @Zayoud  

Sorry for my late feedback.

The STM32WL is a Sub-GHz module that can communicate with any device that use the Same Modulation, same Frequency, ...

The Ping Pong application can be configured to fit on any Wireless STM32 MCU or module. You just have to take care of the HW differences on migration.

RF range is the range of frequency that each MCU can use for communication.

The Sub-GHz parameters are all mentioned on the .h files of the SubGHz_phy folder of each Sub-GHz project (Ping Pong for example).

Hope this is helpful.

Best Regards.

STTwo-32

[Andrew Neil]

---

@Andrew Neil wrote:

---

car & garage door openers tend to be unidirectional - so they certainly won't do a Ping-Pong.

---

And car remote controls tend to use proprietary rolling codes - so you'd have to work out how to implement them...

[Andrew Neil]

---

@Zayoud  wrote:

what is the meaning of the RF range specified in the data sheet of the NUCLEO-WL55JC boards?

---

It actually says, "RF frequency range":

https://www.st.com/resource/en/data_brief/nucleo-wl55jc.pdf 

so that's the range of frequencies (from lowest to highest) at which it works.

Not to be confused with "range" in the sense of the distance over which it can communicate!

[Zayoud]

Hello @Andrew Neil 

I am sorry for my late response

@Andrew Neil wrote:

Do you have any experience with any other microcontroller(s) ?
Electronics in general?

Yes, I have developed two projects with STM32F407 DISC1 and one with STM32f429I-DSICO as ST products, two different types of the Raspberry and the ESP32 in many project in different domain; AI, image processing, Robotics... and I worked in high school with the Arduino. I am still considered as a beginner, but I have an experience to understand some technical details and these are my first steps in RF Domain

---

@Andrew Neil wrote:
It's certainly not the type of thing that the WL are really targetting.

---

You are right, the WL series are targeting the LoRa WAN communication protocol, in fact, they are also able to communicate with the RF devices with RF range from 150 MHz to 960 MHz supporting (G)FSK, (G)MSK, or BPSK modulations.

---

@Andrew Neil wrote:
To answer that, you're going to need to find the specifications for those "RF devices" - in particular,

• On what frequency they operate
• What modulation they use
• What protocol they use over the link.

---

• Frequency Range: SubGHz (190MHz,900MHz)
• The modulation that they use FSK
• What protocol they use over the link: no protocol

---

@Andrew Neil wrote:

---

I think ST provides the Ping-Pong example for all of its LoRa-based products - so no, it's not restricted to just WL

However, car & garage door openers tend to be unidirectional - so they certainly won't do a Ping-Pong.

And they don't do LoRa.

---

yes they don't do pingpong, but I have tried to modify the code in order to read the data from these products, is it possible to read the data from a key using the ping pong application? I know that's not the main purpose of this application, but I think it works, is it?

Best regard,

Zayoud

[Andrew Neil]

---

@Zayoud  wrote:

• What protocol they use over the link: no protocol

---

---

There is no such thing as no protocol.
The "protocol" is simply the definition of how they communicate. You're going to have to know & understand how they communicate in order to capture that communication.

It may be just a very simple protocol - but it is, none the less, a protocol.

@Zayoud

---

 wrote:

is it possible to read the data from a key using the ping pong application?

---

No: the supplied application uses LoRa, and those devices don't.

[Zayoud]

Hello @STTwo-32 

Thanks for the detailed explanation! It clarifies the concept of Sub-GHz communication and modifying the ping pong application.

Here's my understanding:

• The ping pong application can be adapted to various Sub-GHz projects using compatible STM32 MCUs or modules.
• Hardware differences might require adjustments during migration.
• Sub-GHz parameters are defined in the .h files of the SubGHz_phy folder for each project (e.g., ping pong application).

Based on this, I have two questions:

1. Modifying the ping pong application: Can I modify the ping pong application to read data from RF devices using FSK modulation in the 190MHz to 900MHz range, considering I'm using a Nucleo-WL55JC board (which operates in the same range)?
2. Pre-developed application: Are there pre-developed applications specifically designed to establish RF communication with various RF devices (beyond the ping pong application)?

Best regard,

Zayoud

[Zayoud]

yes, I understand that and I mean by no protocol is that a simple protocol of a RF communication.

---

@Andrew Neil wrote:
No: the supplied application uses LoRa, and those devices don't.

I could you please approve that the pingpong application uses just LoRa, because in the one of the application note I found this (LoRa and FSK: frequency shift keying) in the page 44.

[Andrew Neil]

OK - so it looks like that can be configured to just plain FSK modulation, then.

But all that tells you is that Frequency-Shift Keying is applied to the carrier - to communicate with another device, you'd also need to know what deviation is used, what kind of modulating signal is used (eg, Manchester), what the modulation rate is, what the precise carrier frequency is, etc, etc ...

All of these form part of the communication "protocol"