According to
Arduino as a HID Keyboard
Arduino Uno can used as a usb keyboard, Uno has 2 atmega chips, 1x atmega328P as main MCU, 1x atmega8u2 as USB serial
processor to link to PC for programming.
I wanna to make a keyboard too. After I soldered stuffs togather, I found a serious problem though.
The problem is
- I used a
Arduino Nano, notUNO - All my Arduino, Nano or UNO, are Chinese clones, no atmega8u2 but replaced by
CH340G.
I checked the CH340G datasheet, found it not likely* to be turned into a USB-HID.
But I thought again, since PC is so powerful, if it get serial, it's easy to turn them into key strokes. I can use it as a 2nd class keyboard, which linked by serial instead of USB-HID. Weak in BIOS boot time, but will be OK when the OS(windows) is started. What I need is another serial-key software. And I don't need to code myself, because (thanks) someone already did it. I found it in the sf.net serialporttokey.
Put all things togather, it worked! I used my 4x3 keyboard to play a game of Hero of the Storm, with mouse of course.
the 4x3 keyboard mapping is : (for Hero of the Storm)
1 2 3 4
q w e r
z(mount) g(pin map) TAB(talent view)
because Arduino has 11 IO Pin available, which is D2-D12. D0,D1 is used for timing, D13 used for LED on board.
So other keys like a(attack) and space(focus camera) is absent currently.
- use more comfortable buttons.
- use another MCU to implement real USB keyborad.
- more keys to make a full keyboard.