Keyboard driver

[Jimferd]

I'm planning on writing my keyboard driver in C. Do I need to map even the letter keys or just any special functions that I plan on using?

[jrfritz]

I don't understand...but here is my ASCII US scancode array:

// Esc is 27 in ASCII
#define ESC         27
// Backspace in ASCII is '\b'
#define BACKSPACE '\b'
// tab is '\t'
#define TAB '\t'
// newline is '\n'
#define ENTER '\n'
// make newline a enter define, so you can use NEWLINE too
#define NEWLINE ENTER
// Make one for "return" - return to the start of the line:
#define RETURN '\r'

// Define non ASCII special scancodes
// Esc in scancode is 1
#define KESC         1
#define   KF1      0x80
#define   KF2      (KF1 + 1)
#define   KF3      (KF2 + 1)
#define   KF4      (KF3 + 1)
#define   KF5      (KF4 + 1)
#define   KF6      (KF5 + 1)
#define   KF7      (KF6 + 1)
#define   KF8      (KF7 + 1)
#define   KF9      (KF8 + 1)
#define   KF10      (KF9 + 1)
#define   KF11      (KF10 + 1)
#define   KF12      (KF11 + 1)

// Define Cursor Keys
#define   KINS      0x90
#define   KDEL      (KINS + 1)
#define   KHOME      (KDEL + 1)
#define   KEND      (KHOME + 1)
#define   KPGUP      (KEND + 1)
#define   KPGDN      (KPGUP + 1)
#define   KLEFT      (KPGDN + 1)
#define   KUP      (KLEFT + 1)
#define   KDOWN      (KUP + 1)
#define   KRIGHT      (KDOWN + 1)

// "Meta" keys
#define   KMETA_ALT   0x0200   // Alt is pressed
#define   KMETA_CTRL   0x0400   // Ctrl is pressed
#define   KMETA_SHIFT   0x0800   // Shift is pressed
#define   KMETA_ANY   (KMETA_ALT | KMETA_CTRL | KMETA_SHIFT)
#define   KMETA_CAPS   0x1000   // CapsLock is on
#define   KMETA_NUM   0x2000   // NumLock is on
#define   KMETA_SCRL   0x4000   // ScrollLock is on

// Define other keys
#define   KPRNT   ( KRT + 1 )
#define   KPAUSE   ( KPRNT + 1 )
#define   KLWIN   ( KPAUSE + 1 )
#define   KRWIN   ( KLWIN + 1 )
#define   KMENU   ( KRWIN + 1 )

#define   KRLEFT_CTRL      0x1D
#define   KRLEFT_SHIFT      0x2A
#define   KRCAPS_LOCK      0x3A
#define   KRLEFT_ALT      0x38
#define   KRRIGHT_ALT      0x38   // same as left
#define   KRRIGHT_CTRL      0x1D   // same as left
#define   KRRIGHT_SHIFT      0x36
#define   KRSCROLL_LOCK      0x46
#define   KRNUM_LOCK      0x45
#define   KRDEL         0x53

// Define the keypress define
#define KEYPRESS 0x80

// Define the max keyboard buffer
#define MAXKEYBUFFER 64

// Define the keyboard port for getting keys from the keyboard
#define KEYPORT 0x60


// data:
// Define keys:

// Non-Shifted scancodes to ASCII:
static const unsigned char asciiNonSh[] = { NULL, ESC, '1', '2', '3', '4', '5', '6', '7', '8', '9',
'0', '-', '=', BACKSPACE, TAB, 'q', 'w', 'e', 'r', 't', 'y', 'u', 'i', 'o', 'p', '[', ']', ENTER, 0,
'a', 's', 'd', 'f', 'g', 'h', 'j', 'k', 'l', ';', '\'', '`', 0, '\\', 'z', 'x', 'c', 'v', 'b', 'n',
'm', ',', '.', '/', 0, 0, 0, ' ', 0, KF1, KF2, KF3, KF4, KF5, KF6, KF7, KF8, KF9, KF10, 0, 0,
KHOME, KUP, KPGUP,'-', KLEFT, '5', KRIGHT, '+', KEND, KDOWN, KPGDN, KINS, KDEL, 0, 0, 0, KF11, KF12 };

// Shifted scancodes to ASCII:
static const unsigned char asciiShift[] = { NULL, ESC, '!', '@', '#', '$', '%', '^', '&', '*', '(',
')', '_', '+', BACKSPACE, TAB, 'Q', 'W', 'E', 'R', 'T', 'Y', 'U', 'I', 'O', 'P', '{', '}', ENTER, 0,
'A', 'S', 'D', 'F', 'G', 'H', 'J', 'K', 'L', ':', '\"', '~', 0, '|', 'Z', 'X', 'C', 'V', 'B', 'N',
'M', '<', '>', '?', 0, 0, 0, ' ', 0, KF1, KF2, KF3, KF4, KF5, KF6, KF7, KF8, KF9, KF10, 0, 0,
KHOME, KUP, KPGUP, '-', KLEFT, '5', KRIGHT, '+', KEND, KDOWN, KPGDN, KINS, KDEL, 0, 0, 0, KF11, KF12 };

[Jimferd]

Hrmm... that was slightly cryptic now wasnt it. You answered the question tho: Do I need to map all the letter keys (qwertyuiopasdfghjklzxcvbnm) or simply things like -[F1] - [F12]. But appearantly ya do . Thanks.

[ehenkes]

What does this

// Define the keypress define
#define KEYPRESS 0x80

exactly mean? What is 0x80?

[JohnnyTheDon]

Well, that was 7 years ago, so we can't be sure

[egos]

What is 0x80?

It's key up flag in set #1.

Now the good way is using set #2 with key up prefix 0xF0. See keyboard command 0xF0 (it's not a prefix) for more info.

[yemista]

What do you want your keyboard driver to do? Do you want it to just return raw scan codes? Do you want ti to convert to ascii and echo to the screen? Do you want it to be fully functional, or just functional enough to be able to use it?

[djsilence]

Check this out:

http://brokenthorn.com/Resources/OSDev19.html

[jal]

The dead thread revival seems popular nowadays. Maybe the search feature or the post feature should give a big warning :).


JAL