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Sending strings from Feather BLE 32u4 Bluefruit LE to Arduin
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Please be positive and constructive with your questions and comments.

Sending strings from Feather BLE 32u4 Bluefruit LE to Arduin

by snow_leopard on Mon Jan 14, 2019 5:59 pm

Dear Adafruit customer service,

Happy 2019 to you all.

I am attempting to send a string of "hello world" from my Adafruit Feather 32u4 Bluefruit LE ( I shall just call it Adafruit Feather ) to an Arduino Uno R3. I am just trying to learn about ways different boards can communicate with each other, and what are the methods I can use. If there is a good guide out there, please let me know.

I have completed this tutorial https://learn.adafruit.com/introducing- ... data-mode- where I sent strings between the serial monitor ( Feather) to my iphone using Bluefruit LE Connect App ( iPhone).

I have some questions:
On Hardware
1) If I were to send strings from my Adafruit Feather to my Arduino Uno, do I need to connect a transmitter on my Feather? I understand that I need to connect a receiver to my Uno. I am wondering if the Feather already has an inbuilt transmitter that I can use to transmit strings/data to an UNO , since it can transmit strings wirelessly to my phone.

On Code:
Please let me know if my understanding on the below is correct-
In order to send a string ( communicate) from Feather to a UNO, I can do it 2 ways:
1) I can send the character constant of Hello World in the main loop ( Feather), and see "hello world" appearing repeatedly in the serial monitor ( connected to the Uno).
2)Or If i want to manually input strings/ message from a terminal ( maybe from my iPhone), and have the UNO receive the strings ( and display on serial monitor on my laptop), i have to send the strings from my phone to the Feather, and have the Feather transmit it to the UNO. In this case, I am not sure if I need to connect a transmitter to my Feather. If yes, do I just use something common like a RF 433MHZ transmitter/ receiver pair ( transmitter on Feather and receiver on UNO). If I do not need a transmitter connected to my Feather, may I know what receiver would you recommend for the Feather and Uno to communicate?

I would love to hear your recommendation and suggestions. Thank you for your time!

snow_leopard
 
Posts: 22
Joined: Mon Mar 19, 2018 5:56 pm

Re: Sending strings from Feather BLE 32u4 Bluefruit LE to Ar

by oesterle on Mon Jan 14, 2019 6:31 pm

Hi, snow_leopard!

I'm assuming you want to connect the Feather and UNO wirelessly. Unlike your Adafruit Feather 32u4 Bluefruit LE UNO has no built-in Bluetooth LE. Adding Bluetooth LE to the UNO is possible with a breakout board, like the Adafruit Bluefruit LE Shield - Bluetooth LE for Arduino, but since neither device supports central mode, they wouldn't be able talk to each other. (The Adafruit Feather nRF52840 Express does support central mode.)

It would be easier to get your Feather and UNO to talk wirelessly with two of the Adafruit RFM69HCW Transceiver Radio Breakout - 868 or 915 MHz - RadioFruit. On your Feather, you'd also likely need to disable the Bluefruit module via its chip select pin when using this second radio.

Even easier would be to use two of the Adafruit Feather 32u4 RFM69HCW Packet Radio - 868 or 915 MHz - RadioFruit, replacing your Feather and UNO. But those don't have Bluetooth LE. Is connecting to a phone app important for your project?

What are you building?

Cheers,

Eric

oesterle
 
Posts: 601
Joined: Tue Sep 17, 2013 11:32 pm

Re: Sending strings from Feather BLE 32u4 Bluefruit LE to Ar

by snow_leopard on Wed Jan 16, 2019 5:24 pm

Hello Eric,
Thank you for your time and I appreciate your reply.
If I may, I shall ask a couple more questions :)First please let me provide a little bit of a background:
Yes, I am trying to have my Feather & Uno communicate wirelessly. To be specific, I am trying to learn different ways on how I can use my Feather to send and receive strings/ data from other sensors or microcontrollers wirelessly. The tutorial https://learn.adafruit.com/bluefruit-le ... t-terminal teaches me how to send strings from my phone to the Feather and back. I tried that one and now am exploring ways I can have my Feather sending and receive input wirelessly to/ from other sensors or microcontrollers, not using my iPhone at all. Why did I purchased the Feather? Because I wanted to learn how to build a mini toy car and I purchased this kit (https://learn.adafruit.com/bluefruit-fe ... t/overview). And why do I want my Feather to talk to UNO? Because I have a UNO :)
Now, revisiting the earlier question. What I had in mind was- I have the UNO connected to my laptop so that I can view the received strings from Feather on the serial monitor. The UNO does not have to “talk back”. It’s more of a 1 way communication. I assume I still have to use my iPhone Bluefruit app because I have to input the text from somewhere to send to the Feather.
I learned something new from your reply, and I have some questions:
1) You mentioned that “but since neither device supports central mode, they wouldn't be able talk to each other” I assume that you are referring to the Uno and the Bluefruit LE shield? When I connect the Feather to the Bluefruit app on my iPhone, I was in central mode (the app has central or peripheral mode. I read up what a central mode is from this website: (https://devzone.nordicsemi.com/tutorial ... l-tutorial) I don’t fully understand what it is at this point but I am guessing central mode is needed to establish a connection between 2 Bluetooth LE devices.
2) However, why doesn’t Bluefruit LE shield has central mode? How would it be able to connect to other Bluetooth LE devices?
3) Am I right to say that my Feather (I am assuming that is does have a central mode) can only communicate with other Bluefruit LE devices.
4) This also meant that any data sent out from my Feather can be done using Bluetooth LE only? If I want to send data in other form, let say in RF so that my UNO can have a RF receiver and receive them, I would need a RF transmitter and have to turn off Bluetooth LE capability.


Lastly, thank you for asking what about my project. It is very kind of you. If you have the time and interest, please read on and your suggestions and advice would be very welcomed. If not, I still thank you for the time and effort you spent on answering the questions earlier 

As mentioned before, I have built the mini rover and enjoyed the learning process. The rover’s movement can be controlled by the Bluefruit app on my iPhone. As a next step, using the same chassis I have, I am learning how to have the mini rover move itself to a specific spot, let’s say, a specific spot next to a book shelf. I am aware that to do this I need to have a different kind of motor and wheel control. I also think that I need a GPS chip, to let the mini rover knows its current location and to know how far it is from the location it is supposed to go.
I think I would have to learn to:
1) Have the GPS chip send location data to my Feather. I am looking at the Adafruit Ultimate GPS Breakout - 66 channel w/10 Hz updates - Version 3.
2) Have my Feather adjust the wheels to get to the destination. Can you give me a rough idea on how this can be done? I read about things like you need a micro-controller with accelerometer/ gyro features for self-navigating projects, some even mention PID control. I wonder how much can my Feather do to achieve some of this? Or my Feather is not a good choice for a project like this? The reason I was trying to learn how to send data out from my Feather is because- in case I need to send the GPS location value to another device/ micro-controller to perform the location feedback and compare against target destination process. I am also wondering if my Feather is redundant in case like this because I could just have the GPS breakout board send the data directly to the a micro-controller that does the movement feedback control.
3) This is an additional question that has nothing to do with my project, it is more related to a feature of the Feather. When I connect my iPhone to the Feather ( for mini rover project), under the controller page, I can see an option to select “accelerometer”. As the rover move, the X Y Z value changes. I not clear if this means that my Feather has an in built accelerometer? Or is this just something more of just an app feature?

Thank you once again Eric, wishing you a great day!

snow_leopard
 
Posts: 22
Joined: Mon Mar 19, 2018 5:56 pm

Re: Sending strings from Feather BLE 32u4 Bluefruit LE to Ar

by jacks002 on Fri Apr 26, 2019 3:23 am

Wyatt5Beard wrote:
snow_leopard wrote:Dear Adafruit customer service,

Happy 2019 to you all.

I am attempting to send a string of "hello world" from my Adafruit Feather 32u4 Bluefruit LE ( I shall just call it Adafruit Feather ) to an Arduino Uno R3. I am just trying to learn about ways different boards can communicate with each other, and what are the methods I can use. If there is a good guide out there, please let me know.

I have completed this tutorial https://learn.adafruit.com/introducing- ... data-mode- where I sent strings between the serial monitor ( Feather) to my iphone using Bluefruit LE Connect App ( iPhone).

I have some questions:
On Hardware
1) If I were to send strings from my Adafruit Feather to my Arduino Uno, do I need to connect a bluetooth transmitter on my Feather? I understand that I need to connect a receiver to my Uno. I am wondering if the Feather already has an inbuilt transmitter that I can use to transmit strings/data to an UNO , since it can transmit strings wirelessly to my phone.

On Code:
Please let me know if my understanding on the below is correct-
In order to send a string ( communicate) from Feather to a UNO, I can do it 2 ways:
1) I can send the character constant of Hello World in the main loop ( Feather), and see "hello world" appearing repeatedly in the serial monitor ( connected to the Uno).
2)Or If i want to manually input strings/ message from a terminal ( maybe from my iPhone), and have the UNO receive the strings ( and display on serial monitor on my laptop), i have to send the strings from my phone to the Feather, and have the Feather transmit it to the UNO. In this case, I am not sure if I need to connect a transmitter to my Feather. If yes, do I just use something common like a RF 433MHZ transmitter/ receiver pair ( transmitter on Feather and receiver on UNO). If I do not need a transmitter connected to my Feather, may I know what receiver would you recommend for the Feather and Uno to communicate?

I would love to hear your recommendation and suggestions. Thank you for your time!

s the lowest transmitting power really only 13dBm? Where are you planning to use the devices?

It has resolved the problem?

jacks002
 
Posts: 1
Joined: Fri Apr 26, 2019 3:20 am

Please be positive and constructive with your questions and comments.