From previous project "Wac0m Ripoff" that based on STM32 and Teensy ++ 2.0 (with Arduino) I actually going further more by making that project wireless. First time I came up with this idea I'm so confused which microcontroller is really suitable for this project. I start researching for the HC05 and it turns out that you can flash the firmware of RN42 to get the HID capability over Bluetooth. but Its HID descriptor is built into the firmware which is almost impossible to edit the Descriptor without moving next byte to next address (real pain, text file contain address and byte). 

I gave up and move to net thing STM32WB, again I gave up since Bluetooth stack is too advance and I want a "quick" solution. I rejected to use the ESP32 because of how it capable and what I actually use is like a fraction of that. It's not worth to buy it to use in such a simple(?) project.

and my last choice that I picked is the Nordic nRF51822. I coincidentally found this on YouTube channel Hugatry's HackVlog. He use the nRF51822 04 module (A.K.K WT51822-S4AT) with Arduino core. I followed his instruction short after I received the package from seller I bought. I ported the HID code to work as Digitizer (HID description is still the same, but rearrange the usage report to match the packet read from w9013 (no further switch case processing). The digitizer is working just fine except sometime the refresh rate drops significantly, fixed by adding 1 millisecond delay to un-saturate TX rate. 

I confirmed that this work with Windows 10 (my target). Linux and other OSes are untested. but with the same technology standard, I have a high hope that It will works on Linux and other OSes too.