How to use HTS to notify temperature instead of indicate ?

RE: How to use HTS to notify temperature instead of indicate ?

RatheeshT — Tue, 02 Jul 2019 13:54:07 GMT

Hi,

I am using the following

SDK 14.2

Profile - HTS

Device -nRF52832

As per your above suggestion, I have done below to change property to "notify from indicate".

static uint32_t hts_measurement_char_add(ble_hts_t * p_hts, ble_hts_init_t const * p_hts_init)
{
    .
    .
    .
    char_md.char_props.notify = 1;
    
    BLE_GAP_CONN_SEC_MODE_SET_OPEN(&attr_md.read_perm);(added above to memset of attr_md function call)
   
    
    .
    .
    .
}

As extra ,I have done the below also on function ble_hts_measurement_send()

hvx_params.type   = BLE_GATT_HVX_INDICATION;
   to
hvx_params.type   = BLE_GATT_HVX_NOTIFICATION;

After all those modification, it is not working(crashing) in notify property hence I have the following question.

Q1: Whether I have to change anything on services_init() function?

Below are available inside services_init function

BLE_GAP_CONN_SEC_MODE_SET_ENC_NO_MITM(&hts_init.hts_meas_attr_md.cccd_write_perm);
BLE_GAP_CONN_SEC_MODE_SET_NO_ACCESS(&hts_init.hts_meas_attr_md.read_perm);
BLE_GAP_CONN_SEC_MODE_SET_NO_ACCESS(&hts_init.hts_meas_attr_md.write_perm);

BLE_GAP_CONN_SEC_MODE_SET_OPEN(&hts_init.hts_temp_type_attr_md.read_perm);
BLE_GAP_CONN_SEC_MODE_SET_NO_ACCESS(&hts_init.hts_temp_type_attr_md.write_perm);

Q2: Function on_cccd_write() is having function/statement only regarding indication. Anything needs to be changed on this function?

Please let me know your feedback on this.

RE: How to use HTS to notify temperature instead of indicate ?

MartinBL — Fri, 28 Jul 2017 13:35:39 GMT

The values are only simulated. They should change if you press Button 1.

RE: How to use HTS to notify temperature instead of indicate ?

Nivetha — Thu, 27 Jul 2017 09:24:24 GMT

Thanks! It works fine. I have plugged in the HTS service. I have a doubt though. What temperature is actually being transmitted here? Is it the chip's temperature or other value? I see only 37.6 value. Please clarify!

RE: How to use HTS to notify temperature instead of indicate ?

MartinBL — Thu, 27 Jul 2017 06:51:07 GMT

I can't see what would be wrong with the measurements. I don't think there is anything wrong with what you are doing.

RE: How to use HTS to notify temperature instead of indicate ?

Nivetha — Wed, 26 Jul 2017 14:47:12 GMT

got it working! Thanks! But is this the right way to implement? Are these measurements are still valid by using the notify property? Or should I use the intermediate values characteristic to enable the notify temperature values?

RE: How to use HTS to notify temperature instead of indicate ?

Nivetha — Wed, 26 Jul 2017 14:39:24 GMT

yes, I meant the same. I want to use notify, read params just like the battery status to see the temperature.

RE: How to use HTS to notify temperature instead of indicate ?

MartinBL — Wed, 26 Jul 2017 14:37:24 GMT

Are you talking about the Temperature Measurement characteristic in the Health Thermometer service? That should be all you need to enable notification. You won't receive any notification though, before you have also changed the code in on_hts_evt() in main.c to use notification events.

RE: How to use HTS to notify temperature instead of indicate ?

Nivetha — Wed, 26 Jul 2017 13:34:59 GMT

Thanks! But this didn't solve the problem. I guess I have to change few more things in the ble_hts.c to have notifications instead of indication property.

RE: How to use HTS to notify temperature instead of indicate ?

MartinBL — Wed, 26 Jul 2017 13:11:01 GMT

Hi,

I'm not sure if I understand your question, but to use notification you can change this line in the function hts_measurement_char_add() ble_hts.c

char_md.char_props.indicate = 1;

char_md.char_props.notify = 1;

and to enable reading change this:

attr_md.read_perm  = p_hts_init->hts_meas_attr_md.read_perm;

to e.g. this

BLE_GAP_CONN_SEC_MODE_SET_OPEN(&attr_md.read_perm);

If you make these changes though, your device will no longer comply with the HTS profile.