HID over GATT in Beaglebone Black

[Anandan]

Hello,

I would like to implement HID over GATT profile (BLE) in the Beaglebone Black (BBB). The BBB will be used to interface with a laptop/computer running Windows 10 / Linux uBuntu OS. I would like to use the Beaglebone Black to act as an external keyboard for the laptop/computer just like how normal Bluetooth keyboards are currently used to pair up with the computer.

Since the BBB comes with one USB port, I am planning to use the BLE Nano (nRF51822) from Red Bear Labs. The BLE Nano connects to the board via USB port on the BBB. I would like to ask if the ble_app_hids_keyboard example provided by the nRF51 SDK could be compiled and run on this board?

Also, does the BBB need to run BlueZ 5 in order to support BLE? As far as I understand, the nRF51 will run a firmware and it communicates with the board via USB. Hence, BlueZ 5 is not required for this purpose. Please correct me if I am wrong.

Thank you very much in advance!

[Håkon Alseth]

Hi,

If you use the pc-ble-driver, you can control the nRF51 device from a PC (win/linux/mac): github.com/.../pc-ble-driver

This relies on a UART transport layer, and the application is then run on the PC (BeagleBoard in your case) side. Note that the nRF needs to be programmed with the "ble_connectivity" project located in SDK 10.

Cheers, Håkon

[Anandan]

Thank you for your reply.

But actually I am not planning to control the nRF51 from a PC. I want to connect the nRF51 BLE Nano to a USB port on the BBB and then use BBB to send keyboard inputs to the PC. This means that I am planning to implement HoGP on the nRF51.

[Håkon Alseth]

You can compile the pc-ble-driver and run this on a beagleboard if you'd like. You just need to satisfy the dependencies, and it should compile on ARM targets as well.

[Anandan]

Thank you for your reply. I will check out the example. I was actually focusing on the hids keyboard example. May I know the difference between this example and pc-ble-driver?

[Håkon Alseth]

This example fully serializes the SoftDevice, and you can compile your program in C (using pc-ble-driver) on the Beagleboard side to run any project you'd like. Another option can be to add UART to the ble_app_hids_keyboard, and use that to send keystrokes (ie: Beagleboard sends HID-format packet to the nRF, and it relays it over to the BLE central), but this is a more application specific solution.

[Anandan]

Thank you for your reply. I understand it better now. So to enable a more scalable solution, we employ the pc-ble-driver which allows PC application to interact with the SoftDevice. I got the pc-ble-driver definition from the following link: nRF51 Bluetooth Smart GATT/GAP Driver

and the following image explains the definition pictorially (It's the block diagram on the most right of the pic) SoftDevice