Hardfault ble_nus_send_data - SDK 17

[Roei]

Hi,

I've noticed that there was an issue with ble_nus in SDK 15.3 - detailed in this post.

I'm using SDK 17, and in my application, I don't check data_handler != NULL. When BLE_GATTS_EVT_HVN_TX_COMPLETE occurs, I just define ble_nus_evt_t evt and calls p_nus->data_handler. Probably took it from an example, I can't remember.

Is it safe? Should I use something else?

Thanks!

[Einar Thorsrud]

Hi,

This issue is fixed in SDK 17.0.2.

[Roei]

Hi,

Thanks for your response!

Does it fixed event when I don't use on_hvx_tx_complete() function? Also when I just call p_nus->data_handler() without any NULL validation?

Thanks!

[Einar Thorsrud]

Yes you can. The context is the last parameter you pass to NRF_SDH_BLE_OBSERVER.

[Roei]

So it looks like that:

#define BLE_NUS_DEF(_name) \
static ble_nus_t _name; \
NRF_SDH_BLE_OBSERVER(_name ## _obs, \
BLE_NUS_BLE_OBSERVER_PRIO, \
OnBleNusEvent, &_name)

[Einar Thorsrud]

In that case the pointer to _name is your context pointer

[Roei]

What does #define BLE_NUS_DEF(_name) with _name?

[Einar Thorsrud]

I do not really understand the question. If you look at the whole macro it looks like this copied from your previous post and just modified white spaces a bit to make it clearer (note that it is not from SDK 17 which you referred to, but some older SDK):

#define BLE_NUS_DEF(_name) \
static ble_nus_t _name; \
NRF_SDH_BLE_OBSERVER(_name ## _obs, BLE_NUS_BLE_OBSERVER_PRIO, OnBleNusEvent, &_name)

Lets say you call BLE_NUS_DEF like this:

BLE_NUS_DEF(my_nus_instance)

The preprocessor would then translate this to the following (note that I am ignoring that it does the same with NRF_SDH_BLE_OBSERVER here, but it follows the same principle):

static ble_nus_t my_nus_instance;
NRF_SDH_BLE_OBSERVER(_name ## _obs, BLE_NUS_BLE_OBSERVER_PRIO, OnBleNusEvent, &_name)

So you now got a instance of ble_nus_t called my_nus_instance.

I suggest you read up on the C preprocessor if you need to understand more about this.

[Roei]

Ok, I understand. Thanks!