Intelletto dongle

It looks like this dongle is doing something similar to what we want. But it costs almost $50 http://www.intelletto.com/products?id=3004

Nordic USB Dongle

This Nordic USB dongle is what could be programmed into what I need. The Google's OpenSK project could be extended to include this app-controlled Bluetooth Keyboard Emulator. Here is the MakerDiary's board version: https://wiki.makerdiary.com/nrf52840-mdk-usb-dongle/opensk/ https://github.com/makerdiary/nrf52840-mdk-usb-dongle

Here is the original nRF52840 USB Dongle board directly from Nordic. It looks very similar to MakerDiary's board, also it looks like MakerDiary board is a bit smaller in size. Anyways, here is Nordic Dongle: https://www.nordicsemi.com/Software-and-tools/Development-Kits/nRF52840-Dongle

Both MD and Nordic boards are avaialble for sale at around $10 - nice!

Bluetooth dongle with a HID Proxy mode

From our prospective, this is a dongle that translates Bluetooth keyboard into USB HID (aka standard USB Keyboard). Then, in theory, any Bluetooth Keyboard Emulator App should be able to work with such dongle, even in BIOS, even before OS boots up and loads Bluetooth drivers. Surprisingly, it seems like these HID Proxy dongles are rare

ESP32 based projects

I think what I want could also be programmed using ESP32 usb dongles and some software similar to what is used in these projects below. Just including these links so I have it for a reference:

[TW#13919] Bluetooth HID implementation progress? https://github.com/espressif/esp-idf/issues/782

https://github.com/asterics/esp32mousekeyboard

https://github.com/bluekitchen/btstack/tree/master/port/esp32

https://www.crowdsupply.com/rfid-research-group/usbninja

Non-relevant projects that sound confusingly similar

Solo Key - hacker edition - does NOT support Bluetooth, so it is not an option for this project https://solokeys.com/collections/all/products/solo-hacker

USB Ninja - somewhat relevant, but it looks like it is based on Arduino which is I do not think is a good fit here. But it has Android app that talks to USB ninja over bluetooth, so might be worth a look https://www.crowdsupply.com/rfid-research-group/usbninja

Bleuio - can this be programmed into what we want? Maybe yes... https://bleuio.com/index.php#

Some relevant links

https://stackoverflow.com/questions/19781073/sending-data-from-ios-device-to-windows-pc-over-an-bluetooth-hid-dongle?rq=1

https://stackoverflow.com/questions/19781073/sending-data-from-ios-device-to-windows-pc-over-an-bluetooth-hid-dongle?rq=1

https://stackoverflow.com/questions/33171388/bluetooth-usb-smart-dongle-with-hid-support?rq=1

https://github.com/topics/keyboard-emulation

Somewhat relevant terms glossary

Serial Port Profile (SPP) - The Serial Port Profile is a Bluetooth profile that allows for serial communication between a Bluetooth device and a host/slave device. With this profile enabled, you can connect to a Bluetooth module through a serial terminal. This can be used for configuration purposes or for communication purposes. Some pages above talk about "SPP to HID" so it is good to know what is SPP in context of Bluetooth

HID Proxy - the full term is "Bluetooth dongle with a HID Proxy mode" - so I think this is a dongle that translates Bluetooth keyboard into USB HID (aka standard USB Keyboard). Then, in theory, any Android Bluetooth Keyboard Emulator App should be able to work with such dongle, even in BIOS, even before OS boots up and loads Bluetooth drivers. Surprisingly, it seems like these HID Proxy dongles are rare ...