multi link central uart with multiple peripheral

RE: multi link central uart with multiple peripheral

ovrebekk — Thu, 27 Jun 2019 07:30:14 GMT

I haven't had time to work on this example yet, no. Until August I have various business trips and vacation coming up, so it is hard to predict when I will be able to look at this unfortunately.

I you check in again with me in a couple of weeks I will try to provide an updated schedule.

Best regards
Torbjørn

RE: multi link central uart with multiple peripheral

ps_anu — Wed, 26 Jun 2019 06:53:08 GMT

have you tried ?

RE: multi link central uart with multiple peripheral

ovrebekk — Thu, 13 Jun 2019 07:02:09 GMT

Sure thing, I will do my best to help with your questions 🙂

RE: multi link central uart with multiple peripheral

ps_anu — Wed, 12 Jun 2019 08:03:11 GMT

ok i will also try on my best , if i have any doubt i will ask you .Help me in this case

Thanks

RE: multi link central uart with multiple peripheral

ovrebekk — Wed, 12 Jun 2019 07:58:50 GMT

I can try to provide a sample showing how to send a message from one link to the other, but it will have to be a side project that I work on when I have some free time.

It is hard to say when I will have time to provide it.

RE: multi link central uart with multiple peripheral

ps_anu — Tue, 11 Jun 2019 09:40:35 GMT

providing sample code will be better for understanding . where i should declare and how the data will transferred between them . where i should enter the data

RE: multi link central uart with multiple peripheral

ps_anu — Tue, 11 Jun 2019 09:29:53 GMT

Thankyou Torbjorn , but how to do that , how the messages will passed from one to another .

RE: multi link central uart with multiple peripheral

ovrebekk — Tue, 11 Jun 2019 08:40:17 GMT

Yes, this is possible.

On the central side you have to identify the different peripherals by the different items in the m_lbs_c array, where the connection handle of the device corresponds to the index in the array (as I explained in my previous reply).

If you want to use the BLE address to identify the device on the terminal side this is also possible, but then the central will have to do the translation between BLE address and connection handle when receiving messages.

In other words you will need to store a map in memory that maps between BLE address and connection handle.

Best regards
Torbjørn

RE: multi link central uart with multiple peripheral

ps_anu — Thu, 06 Jun 2019 12:29:12 GMT

Hi, Torbjorn

actually i am trying to do a task ,

1.peripherals want to talk to each other (like chating) ,using termite .

2. peripheral can't send the data to other peripheral , in case of that i want to use the central as intermediate in between the peripherals .

3. here many peripherals are present , if one want to send the data to particular peripheral device .

i have some suggestion

can i send the data using mac address or connection handle ?

EXAMPLE if peripheral A wants to send the data to peripheral C , then peripheral A pass the data to central using mac address or connection handle and it should tell to central to convey this data to peripheral C and peripheral C will receive and so on .can we do this ? these things to be achieved without changing the code often .

once the peripherals got connected to central , whoever in connection they should communicate with all of peripherals(using mac address or connection handle ) in termite .

Thanks in advance

RE: multi link central uart with multiple peripheral

ovrebekk — Wed, 05 Jun 2019 08:27:05 GMT

If you are using the multi link central example there is actually an array provided for you already, to keep track of the services of each of the connected devices:

BLE_LBS_C_ARRAY_DEF(m_lbs_c, NRF_SDH_BLE_CENTRAL_LINK_COUNT);

Essentially you will get an array called m_lbs_c, of type ble_lbs_c_s (defined on line 146 of ble_lbs_c.h).

Since the connection handle starts at 0 and increments by 1 for each connected device, the connection handle is used as an index into the array. The first connected device will update m_lbs_c[0], the second device m_lbs_c[1] and so forth.

By default the conn_handle field in the m_lbs_c elements will be initialized to BLE_CONN_HANDLE_INVALID (0xFFFF), but once they are connected the conn_handle will be updated to represent the conn_handle of the connection.

If you want you could extend this struct to contain more information on the device, such as a device name or similar that you want to use to address individual devices.

When sending data over a link you will send a pointer to the m_lbs_c element, such as you can see in the led status send function:

uint32_t ble_lbs_led_status_send(ble_lbs_c_t * p_ble_lbs_c, uint8_t status);

Best regards
Torbjørn

RE: multi link central uart with multiple peripheral

ps_anu — Thu, 30 May 2019 05:31:48 GMT

i am not familiar that much in programming . can you explain me with sample code , i want to send to data by using connection handle . i want to put all connected devices in an array so i can able to transmit the data to particular device

Thank you

RE: multi link central uart with multiple peripheral

ovrebekk — Wed, 29 May 2019 12:54:36 GMT

When a device establishes a connection you will receive the BLE_GAP_EVT_CONNECTED event on the peripheral and central side.

Inside this event you can read the connection handle from the p_ble_evt->evt.gap_evt->conn_handle variable.

Then you can update your local variable associating connection handle with the device from there.

Best regards
Torbjørn

RE: multi link central uart with multiple peripheral

ps_anu — Wed, 29 May 2019 06:44:38 GMT

connection handle are created by the softdevice right , so how to put the connection handle in an array ,by that way i can able to get the particular peripheral to send the data , is it possible ?

Best regards,

pavi

RE: multi link central uart with multiple peripheral

ps_anu — Tue, 28 May 2019 12:08:34 GMT

can we able send the message to particular device (peripheral to peripheral )by manually , similar like this central has been connected 4 peripherals ( A--B---C--D)by using name of the peripheral .In this case peripheral A wants to send the message to the peripheral D, similarly peripheral D wants to send the message to peripheral B , C . so communication has to be done randomly .,whoever in connection in central from end to end , (A B C D ) peripherals have to send the data to each other .is it possible ?

can we resolve by using connection handle .

A--- HAS 0X01 connection handle

B----HAS 0X02 connection handle

C----HAS 0X03 connection handle so on

example if A want to send the data to C

can i able to enter manually like ------ A (0X01) , hello to B(0x02)

or else is there any other way to communicate the peripheral to peripheral

Best regards

pavi

RE: multi link central uart with multiple peripheral

ps_anu — Tue, 28 May 2019 05:37:01 GMT

Thank your explanation , how to send the data via uart using connection handle of specific device

Best regards ,

pavi

RE: multi link central uart with multiple peripheral

ovrebekk — Mon, 27 May 2019 14:35:46 GMT

Every link on the central side will be identified by a unique connection handle, which is a 16-bit value that starts at 0 and is incremented for each additional link.

If you want you can map the connection handle to something else, such as the BLE address or a device name, but whenever you want to send something to a specific device you need to use the connection handle of that device to address it.

It is important to know that each device could get a different connection handle each time it connects to the central, so the central will have to update the connection handle/BLE address map continuously as devices are disconnected and connected.

It is also important to know that the connection handle for a link is not necessarily the same on the peripheral and central side (a peripheral with only one link to a master will only use connection handle 0).

Best regards
Torbjørn