how nRF52 chip connects to another Bluetooth device?

[huaminhtuan]

Hi everyone,

I am using board PCA10040 v1.1.0, softdevice 13.0.0, Eclipse Oxygen. I am trying to connect my board with a device call Daydream controller.

There is also a emulator app of that device on Android phones.

It is said that there is BLE 4.2 on the Daydream device. Could you help me how can I set up a connection with that device using my PCA10040 board, please?

Thanks for reading.

[endnode]

Hi,

There won't be really easy 5-minute way but if you understand how GAP and GATT layers work then you could see some of GAP Central examples in nRF5 SDK which are basically doing what you should do in your nRF5x embedded FW (on top of S13x Nordic SoftDevice aka BLE stack). Probably using nRF Connect App for Android or iOS (downloadable from official app stores) and trying to detect your daydream controller, connecting and observing if it really is GAP Peripheral + GATT Server device (as it looks from the first sight). If this is verified then you have long journey in front of you and several possible ways: you can either try to get some documentation to the BLE protocol and implement it directly or you can decompile Android app (if this is your preference and skill-set) to get the protocol and implement it in Nordic stack API inside nRF5x or you can try to reverse engineer the protocol by using BLE radio analyzer/sniffer and simply observing the communication (including decrypting of BLE Security Manager layer as you can intercept pairing session and extract long term keys). Note that if there are any complex things like applicative layer security (encryption/signature scheme for confidentiality&authentication) then it can be really painful job.

Good luck, happy hacking!

[huaminhtuan]

Hi endnode, Thanks for helping me. I will try and if I have some trouble, I will post my question in this thread :D

[huaminhtuan]

Hi endnode, I tried the tutorial "Bluetooth low energy Services, a beginner's tutorial" with my v13.0.0 sdk. But it seems that the modules "device_manager" and "pstorage" is removed and replaced by "peer_manager" and "fstorage". Is there any examples or tutorials to show how to migrating between them?

[endnode]

Hi, I'm afraid SDK and examples are in constant development so things like this happen. Nordic guys are trying to keep up with updating tutorials but it's not easy. I don't have any specific hints to these modules but you can search through BLOG zone, Nordic GitHub projects and Q&As here on the forum, I'm sure someone already pointed these changes out. In the end all the tutorials are based on SDK examples, aren't they? And SDK examples are up-to-date with latest SDK modules/libraries/drivers...

[huaminhtuan]

Hi endnode, I am trying to create my own service. I have tried the ble_app_uart example, the service tuorial and the migrating from device_manger to peer_manager. But I get the error "NRF_ERROR_NO_MEM" from sd_ble_uuid_vs_add function. Can you give me some advices? Thanks

[endnode]

And have you searched for this type of error on the forum? I have secret for you: it's number one problem and solution is always the same: follow examples and SD migration guide to always find the right RAM limits for SD and APP.