Filtering advertisements based on target apperance

Question

I am currently struggling with filtering based on appearance using the Scanning module. I have a beacon that advertises some dummy data, appearance and service UUID. With the scanning module I was able to filter this advertisement from other advertisements by testing it in an environment with a lot of BLE devices. However, whenever I try to filter both service UUID and appearance or just appearance I do not receive any advertisements that matches with these filters. The code below works fine. err = bt_scan_filter_add(BT_SCAN_FILTER_TYPE_UUID, &beacon_service_uuid);
	if (err) {
 printk("Service UUID scan filter cannot be set (err %d)
", err);

return err;
	}
	
err = bt_scan_filter_enable(BT_SCAN_UUID_FILTER, true);
	if (err) {
 printk("UUID filters cannot be enabled (err %d)
", err);
 return err;
	}
 The following however does not work err = bt_scan_filter_add(BT_SCAN_FILTER_TYPE_APPEARANCE, &beacon_appearance_uuid);
	if (err) {
 printk("Appearance UUID scan filter cannot be set (err %d)
", err);
 return err;
	}

err = bt_scan_filter_enable(BT_SCAN_APPEARANCE_FILTER, true);
	if (err != 0) {
 printk("Scan filters cannot be enabled (err %d)
", err);
 return err;
	} I can try to do the filtering whenever I parse the data, but I would like to see if I can already filter advertisements with the filters.

Susheel Nuguru · Accepted Answer

We found the issue. we found that the issue is in ncs\v2.5.0
rf\subsys\bluetooth\scan.c 
 static bool find_appearance(const uint8_t *data,
 uint8_t data_len,
 const uint16_t *appearance)
{
	if (data_len != sizeof(uint16_t)) {
 return false;
	}

	uint16_t decoded_appearance = sys_get_be16(data);

	if (decoded_appearance == *appearance) {
 return true;
	}

	/* Could not find the appearance among the encoded data. */
	return false;
} 
 You need to change the sys_get_be16 -> sys_get_le16 
 This is a bug, so I will create an internal bug tracker.

Filtering advertisements based on target apperance

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