Nus profile seems to cause system reset if the data length too long.

RE: Nus profile seems to cause system reset if the data length too long.

Petter Myhre — Fri, 18 Nov 2016 12:15:47 GMT

Great! I tried to clean this question up a bit, so it can be useful to others. Could you accept my answer by clicking the grey circle next to it?

RE: Nus profile seems to cause system reset if the data length too long.

Ted — Fri, 18 Nov 2016 03:14:56 GMT

Hi Petter, Thank you very much. It works fine.

RE: Nus profile seems to cause system reset if the data length too long.

Petter Myhre — Thu, 17 Nov 2016 12:45:37 GMT

Thank you. Very helpful. Try the following:

if(p_ble_evt->header.evt_id == BLE_EVT_USER_MEM_REQUEST)
{
    err_code = sd_ble_user_mem_reply(m_nus.conn_handle, NULL);
    APP_ERROR_CHECK(err_code);
}
if(p_ble_evt->header.evt_id == BLE_GATTS_EVT_RW_AUTHORIZE_REQUEST)
{
    ble_gatts_rw_authorize_reply_params_t rw_authorize_reply_params;
    
    memset(&rw_authorize_reply_params, 0, sizeof(rw_authorize_reply_params));
    
    rw_authorize_reply_params.type = BLE_GATTS_AUTHORIZE_TYPE_WRITE;
    
    if(p_ble_evt->evt.gatts_evt.params.authorize_request.request.write.op == BLE_GATTS_OP_EXEC_WRITE_REQ_CANCEL)
    {
        rw_authorize_reply_params.params.write.gatt_status = BLE_GATT_STATUS_SUCCESS;
    }
    else
    {
        rw_authorize_reply_params.params.write.gatt_status  = BLE_GATT_STATUS_ATTERR_WRITE_NOT_PERMITTED;
    }
    err_code = sd_ble_gatts_rw_authorize_reply(m_nus.conn_handle, &rw_authorize_reply_params);
    APP_ERROR_CHECK(err_code);
}

RE: Nus profile seems to cause system reset if the data length too long.

Ted — Thu, 17 Nov 2016 09:43:12 GMT

I have posted it on top. Please have a look.

RE: Nus profile seems to cause system reset if the data length too long.

Petter Myhre — Thu, 17 Nov 2016 06:46:53 GMT

Please edit your question and include the sniffer data and the PNG.

RE: Nus profile seems to cause system reset if the data length too long.

Ted — Thu, 17 Nov 2016 04:21:23 GMT

I cannot still make the nordic usb dongle to work properly. But I use TI's usb dongle I have capture the data. Can you read TI's sniffer data? If you can't. Can I extract the error packet to a PNG file to you? How to post it?

RE: Nus profile seems to cause system reset if the data length too long.

Ted — Wed, 16 Nov 2016 04:25:36 GMT

I cannot make my usb dongle work properly. I'll post the sniffer data if I capture the data properly.

RE: Nus profile seems to cause system reset if the data length too long.

Petter Myhre — Mon, 14 Nov 2016 13:27:32 GMT

Ok. I'm not sure why you get the error. Can you do a sniffer trace with the nRF Sniffer? Also, when you get the error, what are all the parameters in ble_gatts_evt_rw_authorize_request_t struct that comes with the BLE_GATTS_EVT_RW_AUTHORIZE_REQUEST event?

RE: Nus profile seems to cause system reset if the data length too long.

Ted — Mon, 14 Nov 2016 06:21:18 GMT

Oh, it is very strange. I use your code and then I send 22-byte data. I receive BLE_EVT_USER_MEM_REQUEST event 1 time and call the API of sd_ble_user_mem_reply(m_conn_handle, NULL). Then I get first BLE_GATTS_EVT_RW_AUTHORIZE_REQUEST event and call the API of sd_ble_gatts_rw_authorize_reply(m_conn_handle, &rw_authorize_reply_params). I get the error code == 0. (success). Then I get second BLE_GATTS_EVT_RW_AUTHORIZE_REQUEST event and call the API of sd_ble_gatts_rw_authorize_reply(m_conn_handle, &rw_authorize_reply_params). I get the error code == 7. (failure. system reset).

RE: Nus profile seems to cause system reset if the data length too long.

Petter Myhre — Fri, 11 Nov 2016 10:04:15 GMT

Strange, I tested the following code in ble_evt_dispatch(), and I'm not getting any error code:

if(p_ble_evt->header.evt_id == BLE_EVT_USER_MEM_REQUEST)
{
    err_code = sd_ble_user_mem_reply(m_nus.conn_handle, NULL);
    APP_ERROR_CHECK(err_code);
}
if(p_ble_evt->header.evt_id == BLE_GATTS_EVT_RW_AUTHORIZE_REQUEST)
{
    ble_gatts_rw_authorize_reply_params_t rw_authorize_reply_params;
    
    memset(&rw_authorize_reply_params, 0, sizeof(rw_authorize_reply_params));
    
    rw_authorize_reply_params.type = BLE_GATTS_AUTHORIZE_TYPE_WRITE;
    
    rw_authorize_reply_params.params.write.gatt_status  = BLE_GATT_STATUS_ATTERR_WRITE_NOT_PERMITTED;

    err_code = sd_ble_gatts_rw_authorize_reply(m_nus.conn_handle, &rw_authorize_reply_params);
    APP_ERROR_CHECK(err_code);
}

RE: Nus profile seems to cause system reset if the data length too long.

Ted — Fri, 11 Nov 2016 03:15:33 GMT

I tested all gatt_status from BLE_GATT_STATUS_SUCCESS to BLE_GATT_STATUS_ATTERR_CPS_OUT_OF_RANGE. I got an error code = 7 from the reply of the function of sd_ble_gatts_rw_authorize_reply at each gatt_status. Some gatt_status got a BLE_GATTS_EVT_RW_AUTHORIZE_REQUEST event, and some gatt_status got it twice. Can I use my code I post yesterday? Does it has any side effect?

RE: Nus profile seems to cause system reset if the data length too long.

Petter Myhre — Thu, 10 Nov 2016 12:26:47 GMT

Ok. What if you use BLE_GATT_STATUS_ATTERR_WRITE_NOT_PERMITTED instead?

RE: Nus profile seems to cause system reset if the data length too long.

Ted — Thu, 10 Nov 2016 08:11:38 GMT

Yes, If I respond with sd_ble_user_mem_reply( p_ble_evt->evt.gap_evt.conn_handle, NULL), I receive a BLE_GATTS_EVT_RW_AUTHORIZE_REQUEST event. If I respond with auth_reply.params.write.gatt_status = BLE_GATT_STATUS_ATTERR_REQUEST_NOT_SUPPORTED and auth_reply.type = BLE_GATTS_AUTHORIZE_TYPE_WRITE. Then I call the function of sd_ble_gatts_rw_authorize_reply(p_ble_evt->evt.gatts_evt.conn_handle, &auth_reply) like I post on 3rd Nov, and it will return error code = 7 (NRF_ERROR_INVALID_PARAM, cause system reset).

If I change the code as follows, the system won't cause system reset. I want to know it is correct or not? How may bytes I need to use? Which event I will get at each message segmentation to get data? LightBlue on BlueiPhone and nRFConnect on Android phone have the same result.

case BLE_EVT_USER_MEM_REQUEST:
{
    static ble_user_mem_block_t mem_block;
    static uint8_t buffer[40];
    mem_block.len = 40;
    mem_block.p_mem = &buffer[0];
    err_code = sd_ble_user_mem_reply(m_conn_handle, &mem_block);
    break;
}
case BLE_EVT_USER_MEM_RELEASE:
{
    // call an error respond function.
    break;
}

RE: Nus profile seems to cause system reset if the data length too long.

Petter Myhre — Wed, 09 Nov 2016 14:25:20 GMT

I want to help you, but I don't have an iOS device here to test with, so I'm not 100% sure what iOS is doing. Providing a sniffer trace would really help, you can use the nRF Sniffer. If you respond with sd_ble_user_mem_reply(), you should receive a BLE_GATTS_EVT_RW_AUTHORIZE_REQUEST event, as you see here. Are you receiving this event? If you do, you can try to call sd_ble_gatts_rw_authorize_reply() with gatt_status set to something else than BLE_GATT_STATUS_SUCCESS, for example BLE_GATT_STATUS_ATTERR_INVALID_ATT_VAL_LENGTH or BLE_GATT_STATUS_ATTERR_REQUEST_NOT_SUPPORTED. However, I do not know how iOS will respond to this.

RE: Nus profile seems to cause system reset if the data length too long.

Ted — Wed, 09 Nov 2016 01:35:05 GMT

I am using ble_uart example. I'll get the event of BLE_EVT_USER_MEM_REQUEST at the function of on_ble_evt(ble_evt_t * p_ble_evt) if I send 22 characters at iPhone5 using LightBlue. It will cause to system reset after 30 seconds if I don't process it at the event of BLE_EVT_USER_MEM_REQUEST. It will also cause to system reset after 30 seconds if I call the function of sd_ble_user_mem_reply(p_ble_evt->evt.gap_evt.conn_handle, NULL) at the event of BLE_EVT_USER_MEM_REQUEST. I cannot protect my project against causing to system reset if I send over 20 characters at iPhone5 using LightBlue. Can anyone do me a faver? I don't need to support long writes.

RE: Nus profile seems to cause system reset if the data length too long.

Ted — Tue, 08 Nov 2016 01:28:02 GMT

I don't want to support long writes. I just want to protect my project against system reset. Do you have easy way to do it?

RE: Nus profile seems to cause system reset if the data length too long.

Petter Myhre — Fri, 04 Nov 2016 11:08:45 GMT

So you are triggering long write/queued write by trying to write more than 20 bytes, which is not supported by nus, see this for more information. You get event 2, which is BLE_EVT_USER_MEM_REQUEST. If you want to support long writes you need to modify the example. You need to handle the events and increase the maximum length of the TX characteristic value. In most cases it is better to split your data into 20 bytes pieces and reassemble the data in the peer application.

RE: Nus profile seems to cause system reset if the data length too long.

Ted — Fri, 04 Nov 2016 09:58:46 GMT

I use ble_app_uart example to test. I modified code to print event mesaage. The code is as follows.

static void ble_evt_dispatch(ble_evt_t * p_ble_evt)
{
    ***printf("event=%d\n", p_ble_evt->header.evt_id);***
    ble_conn_params_on_ble_evt(p_ble_evt);
    ble_nus_on_ble_evt(&m_nus, p_ble_evt);
    on_ble_evt(p_ble_evt);
    ble_advertising_on_ble_evt(p_ble_evt);
    bsp_btn_ble_on_ble_evt(p_ble_evt);
}

I got some debug mesages from UART as follows:

UART Start!

event=16

event=80 <-- sent sent 5 characters

12345

event=80 <-- sent sent 10 characters

1234567890

event=80 <-- sent sent 20 characters

12345678901234567890

event=2 <-- sent 22 characters BLE disconnect from phone

The project of ble_app_uart seems same issue.

Our QA team is makeing critical test. They sent unpredictable data to test it.

RE: Nus profile seems to cause system reset if the data length too long.

Petter Myhre — Fri, 04 Nov 2016 08:10:20 GMT

Thirdly, I strongly recommend to test the functionality you want with the ble_app_uart example first, then we have common starting point, and it is easier to figure things out.

RE: Nus profile seems to cause system reset if the data length too long.

Petter Myhre — Fri, 04 Nov 2016 08:08:46 GMT

Ok. So you get into trouble when you are trying to write more than 20 bytes into the TX characteristic. Firstly, as I mentioned above, the maximum ATT MTU with the S130 v2 is 23 bytes, the header is 3 bytes, so up to 20 bytes of data is allowed in one operation. So you are probably triggering long write/queued write by trying to write more than 20 bytes, which is not supported by nus, see this for more information. Secondly, the maximum length of the TX characteristic value is 20 bytes, so if you want to actually do a long write you have to change this. But in most cases it is better to split your data into 20 byte pieces and reassemble the data in the peer application.

RE: Nus profile seems to cause system reset if the data length too long.

Hieu — Fri, 04 Nov 2016 04:22:17 GMT

I am afraid I don't know enough to help beyond this.

It also is not clear to me why a Long Write to NUS would result in authorization request, because the write permission for the NUS RX characteristics is set to open... My only (unhelpful) guess is that because NUS RX characteristic's maximum length is 20, writing more than 20 create some unknown conflicts...

Hope someone could help you soon.

RE: Nus profile seems to cause system reset if the data length too long.

Ted — Fri, 04 Nov 2016 03:13:53 GMT

The error return code of sd_ble_gatts_rw_authorize_reply is 7 (NRF_ERROR_INVALID_PARAM). I don't understand why I haven't received the event of BLE_GATTS_EVT_RW_AUTHORIZE_REQUEST when the data length is less than or equal 20 bytes. I will receive the event of BLE_GATTS_EVT_RW_AUTHORIZE_REQUEST when the data length is great than 20 bytes. My project is modified from the project of ble_app_hrs_rscs_relay_pca10028 of SDK11. (It locations at examples\ble_central_and_peripheral\experimental\ble_app_hrs_rscs_relay\pca10028\s130\arm5_no_packs) I also modified ble_nus.c.

RE: Nus profile seems to cause system reset if the data length too long.

Hieu — Thu, 03 Nov 2016 09:18:56 GMT

First off, I gotta admit I am unfamiliar with these authorization events. So I apologize before hand, but I can't guarantee help. (Also means anyone who know more should feel free to step in).

What error code is being returned? You can see the list of possible error at the sd_ble_gatts_rw_authorize_reply() function's documentation.

Also, where did you get the BLE_GATTS_EVT_RW_AUTHORIZE_REQUEST handling code from? I believe it is not from the NUS example.

RE: Nus profile seems to cause system reset if the data length too long.

Ted — Thu, 03 Nov 2016 08:28:54 GMT

Sorry, I have no good skill with Nordic platform. I follow your instrument to trace the code. I got an event of BLE_GATTS_EVT_RW_AUTHORIZE_REQUEST if the data length is great than 20 bytes. (at APP_ERROR_CHECK)

But if the data length isn't great than 20 bytes I don't receive the event of LE_GATTS_EVT_RW_AUTHORIZE_REQUEST and system work fine.

Could you guide me how to trace it and fix this wrong I made?

static void on_ble_peripheral_evt(ble_evt_t * p_ble_evt)
{
    uint32_t err_code;
    switch (p_ble_evt->header.evt_id)
    {
        case BLE_GAP_EVT_CONNECTED:
...
             break; //BLE_GAP_EVT_CONNECTED
        case BLE_GAP_EVT_DISCONNECTED:
...
            break;//BLE_GAP_EVT_DISCONNECTED
        case BLE_EVT_USER_MEM_REQUEST:
...
            break;//BLE_EVT_USER_MEM_REQUEST
        case BLE_GATTS_EVT_RW_AUTHORIZE_REQUEST:
        {
            ble_gatts_rw_authorize_reply_params_t auth_reply;
            if(p_ble_evt->evt.gatts_evt.params.authorize_request.type
               != BLE_GATTS_AUTHORIZE_TYPE_INVALID)
            {
                if ((p_ble_evt->evt.gatts_evt.params.authorize_request.request.write.op
                     == BLE_GATTS_OP_PREP_WRITE_REQ)
                    || (p_ble_evt->evt.gatts_evt.params.authorize_request.request.write.op
                     == BLE_GATTS_OP_EXEC_WRITE_REQ_NOW)
                    || (p_ble_evt->evt.gatts_evt.params.authorize_request.request.write.op
                     == BLE_GATTS_OP_EXEC_WRITE_REQ_CANCEL))
                {
                    if (p_ble_evt->evt.gatts_evt.params.authorize_request.type
                        == BLE_GATTS_AUTHORIZE_TYPE_WRITE)
                    {
                        auth_reply.type = BLE_GATTS_AUTHORIZE_TYPE_WRITE;
                    }
                    else
                    {
                        auth_reply.type = BLE_GATTS_AUTHORIZE_TYPE_READ;
                    }
                    auth_reply.params.write.gatt_status = APP_FEATURE_NOT_SUPPORTED;
                    err_code = ***sd_ble_gatts_rw_authorize_reply(p_ble_evt->evt.gap_evt.conn_handle,&auth_reply);
                    APP_ERROR_CHECK(err_code);  -->fail at here***
                }
            }
        }break;//BLE_GATTS_EVT_RW_AUTHORIZE_REQUEST
        default:
            // No implementation needed.
            break;
    }
}

RE: Nus profile seems to cause system reset if the data length too long.

Hieu — Thu, 03 Nov 2016 02:09:28 GMT

Uh.. you probably don't want to follow up using an answer.

Anyway, I have never encountered any system reset due to SoftDevice, whether I use custom BLE services or nRF SDK's BLE Service.

Following @petter 's suggestion, you should look at all places APP_ERROR_CHECK is used. Or quicker, add the preprocessor DEBUG in compiling option. This change APP_ERROR_CHECK to trap the firmware in an infinite loop at errors rather than reset the system. You can then use debug mode and see where the system freeze. Also when it froze, take a look at app_error.c. There are some global variables storing which line in which file trigger the error.