sending ASCII bytes through Mesh between a nrf52840 development kit and two dongle

[Sama]

Hello everyone,

I am new and tried some example on the nrf52840 devkit and dongle, including light switch example. 

I am now going to send some ASCII bytes through the mesh between three boards and receive a verification message in the client side.

Actually I thought this is done by adding  sent and receive functions in the switch light example (server and client) inside the main.c. But after searching the devzone I was completely confused.

I read these discussions but I could not modify the code correctly.

https://devzone.nordicsemi.com/f/nordic-q-a/29836/send-and-receive-a-string-via-access-layer

https://devzone.nordicsemi.com/f/nordic-q-a/31256/receiving-simple-message-mesh/123576

https://devzone.nordicsemi.com/f/nordic-q-a/39629/how-to-send-data-to-all-node-over-mesh

https://devzone.nordicsemi.com/f/nordic-q-a/47611/sending-data-over-the-mesh-network

https://devzone.nordicsemi.com/f/nordic-q-a/46092/send-string-in-a-mesh-with-nrf52dk/

I have error on 

simple_message_OPCODE_SEND
and 
the address_set function
and also in the server side:

status= access_model_publish(m_server.model_handle, &msg);

I think there are some different in the new version of the nRF52 SDK for mesh V.5 I used.

Could you please help me on this topic.

Thank you,

Sama

[Mttrinh]

Hi, 

There have been made a lot of changes and improvements from Mesh SDK v1.0.0 to v5.0.0. Unfortunately, we don't have any official examples for sending strings over mesh. The links you are referring to is a great starting point and gives you an idea of how you can do this. 

When it comes to the error you get, can you get more details? What function gives which errors? What kinda error do you get? Can you provide some debug logs?

[Mttrinh]

Hi,

Have you had any progress with this? 

You should put the send_my_message() function outside the button_event_handler(). And the void address_set(uint16_t addr) can be added to main.c.

Additional you should add these static variables and include as well in your main.c:

#include "simple_message_common.h"
#include "simple_on_off_server.h"

static simple_on_off_server_t m_server;

static dsm_handle_t m_central_handle;

Thanks for your patience.

[Mttrinh]

Hi,

Regarding the error 7, you probably haven't bound model to appkey or publish address haven't been set.

Sama said:

Are you sure there is no need to change other codes, as I see in this case that the Generic OnOff and a few lines have been modified?

I don't think you have to make the changes that are being made on the client in that thread, but you need make changes on the server side though.

I will try setting up the example with the latest SDK version on my side. It might take some time, I will update you as soon as possible.

[Mttrinh]

Hi,

I have modified the light switch example in our latest Mesh SDK v5.0.0. You can search for "modified" to see what I have modified on the client and server.

I used the nRF Mesh app to provision the devices, bind the models to appkey and set the publish address. 

Push button 1 on the client board and you will see that a "Hello" message will be received on the server.

nrf5_SDK_for_Mesh_v5.0.0_src_.rar

[Sama]

Hi,

Thank you very much.

I will try that.

Br,

Sama

[Sama]

Hi,

Thank you again for the modification of the codes which workes well.

1) I wonder that why the handle_send_status function is rune twice in the server-side as you see in the log:

<t: 0>, main.c, 370, ----- BLE Mesh Light Switch Server Demo -----
<t: 12177>, main.c, 326, Initializing and adding models
<t: 12180>, main.c, 180, App OnOff Model Handle: 2
<t: 12183>, main.c, 185, App DTT Model Handle: 3
<t: 12187>, main.c, 191, App Scene Model Handle: 5
<t: 12244>, main.c, 304, Node Address: 0x0002
<t: 12247>, mesh_app_utils.c, 66, Device UUID (raw): 137FF47B11294702B381A62F60654E45
<t: 12250>, mesh_app_utils.c, 67, Device UUID : 137FF47B-1129-4702-B381-A62F60654E45
<t: 12279>, main.c, 420,
-------------------------------------------------------------------------------
Button/RTT 1) LED state will toggle and inform clients about the state change.
Button/RTT 4) Clear all the states to reset the node.
-------------------------------------------------------------------------------
<t: 12745>, app_onoff.c, 154, msg: SET: 0
<t: 169757>, generic_onoff_server.c, 274, ASCII Message: Hello
<t: 169760>, generic_onoff_server.c, 280, length of buffer_RX: 5
<t: 169770>, generic_onoff_server.c, 325, Status : 0
<t: 172383>, generic_onoff_server.c, 274, ASCII Message: Hello
<t: 172385>, generic_onoff_server.c, 280, length of buffer_RX: 5
<t: 172395>, generic_onoff_server.c, 325, Status : 0

2) To send large data through the mesh, I used ".force_segmented = true" option in the definition of my message, allowing me to send 360-byte data. Is this way correct?
Is there any solution to send more bytes?

3) Is it possible to send the data to a specific node? Actually, how can I send my message to a specific device, and how can I set the address inside the codes? 

Br,
Sama

[Mttrinh]

Hi,

1. Have you made any changes to the project? You are using the nRF Mesh to provision the devices, bind the models to appkey and set the publish address, correct? I don't see this on my side.

2. Any packet with size larger than 11 bytes (including header) will be split into segmented messages automatically. But the maximum possible segmented payload size is 380 so it will fail if you have a higher payload. Note that Mesh is not optimal for sending/streaming a lot of data.

3. Yes, you can send data to a specific node by publishing to their unicast address. You can do this in the nRF Mesh app.