The Keyboard Driver #

The keyboard driver does the task of reading the input coming from the keyboard and writing it to the screen using the FrameBuffer driver. The keyboard driver uses I/O ports mapped to memory addresses 0x64 and 0x60 to read the data coming from the keyboard.

Every time a key on the keyboard is pressed, 0x64 is set and an 8 bit integer is available in 0x60 which is passed to a massive switch case that appropriately writes the text on the screen. The entered text is also stored in a character buffer, the pointer to this buffer is returned when the enter key is pressed.

The driver is wrapped in the KEYBOARD_DRIVER namespace with just one function,

• char *readInput(FrameBuffer::Writer &p, int mode = 1)

  Returns a char* to the entered text while writing those characters to the FrameBuffer::Writer passed.

  mode=1 is normal mode and mode=0 is password mode, just prints *.

Refer the source code for more details on the implementation.