Turns Caps Lock LED on in Windows

[Penooker]

This is for people who want to know if the Macbook Air is on, because Jobs decided to remove the power indicator led. It turns on the Caps Lock LED in Windows, without actually changing the state of Caps Lock.

Stupid, and lame, and even lamer that I need one. This script is for AutHotKey, so grab that first. The script is an adapted and fixed version of the script here (http://www.autohotkey.com/forum/topic10532.html)

; Keyboard LED control (capslock/numlock/scrolllock lights)
;   http://www.autohotkey.com/forum/viewtopic.php?t=10532

; USAGE: KeyboardLED(LEDvalue,"Cmd")  ; LEDvalue: ScrollLock=1, NumLock=2, CapsLock=4 ; Cmd = on/off/switch
#SingleInstance



Loop ; flash all LEDs
  {
  KeyboardLED(4,"on")
  Sleep, 30000
  }



KeyboardLED(LEDvalue, Cmd)  ; LEDvalue: ScrollLock=1, NumLock=2, CapsLock=4 ; Cmd = on/off/switch
{
  Static h_device
  If ! h_device ; initialise
    {
    device =\Device\KeyBoardClass1
    SetUnicodeStr(fn,device) 
    h_device:=NtCreateFile(fn,0+0x00000100+0x00000080+0x00100000,1,1,0x00000040+0x00000020,0)
    }

  VarSetCapacity( output_actual, 4, 0 )
  input_size = 4
  VarSetCapacity( input, input_size, 0 )

  If Cmd= switch  ;switches every LED according to LEDvalue
   KeyLED:= LEDvalue
  If Cmd= on  ;forces all choosen LED's to ON (LEDvalue= 0 ->LED's according to keystate)
   KeyLED:= LEDvalue | (GetKeyState("ScrollLock", "T") + 2*GetKeyState("NumLock", "T") + 4*GetKeyState("CapsLock", "T"))
  If Cmd= off  ;forces all choosen LED's to OFF (LEDvalue= 0 ->LED's according to keystate)
    {
    LEDvalue:= LEDvalue ^ 7
    KeyLED:= LEDvalue & (GetKeyState("ScrollLock", "T") + 2*GetKeyState("NumLock", "T") + 4*GetKeyState("CapsLock", "T"))
    }
  ; EncodeInteger( KeyLED, 1, &input, 2 ) ;input bit pattern (KeyLED): bit 0 = scrolllock ;bit 1 = numlock ;bit 2 = capslock
  input := Chr(1) Chr(1) Chr(KeyLED)
  input := Chr(1)
  input=
  success := DllCall( "DeviceIoControl"
              , "uint", h_device
              , "uint", 0x000B0008

;CTL_CODE( 0x0000000b     ; FILE_DEVICE_KEYBOARD
;                        , 2
;                        , 0             ; METHOD_BUFFERED
;                        , 0  )          ; FILE_ANY_ACCESS
              , "uint", &input
              , "uint", input_size
              , "uint", 0
              , "uint", 0
              , "uint", &output_actual
              , "uint", 0 )
}

CTL_CODE( p_device_type, p_function, p_method, p_access )
{
  Return, ( p_device_type << 16 ) | ( p_access << 14 ) | ( p_function << 2 ) | p_method
}


NtCreateFile(ByRef wfilename,desiredaccess,sharemode,createdist,flags,fattribs)
{ 
  VarSetCapacity(fh,4,0) 
  VarSetCapacity(objattrib,24,0) 
  VarSetCapacity(io,8,0) 
  VarSetCapacity(pus,8) 
  uslen:=DllCall("lstrlenW","str",wfilename)*2 
  InsertInteger(uslen,pus,0,2) 
  InsertInteger(uslen,pus,2,2) 
  InsertInteger(&wfilename,pus,4) 
  InsertInteger(24,objattrib,0) 
  InsertInteger(&pus,objattrib,8) 
  status:=DllCall("ntdll\ZwCreateFile","str",fh,"UInt",desiredaccess,"str",objattrib,"str",io,"UInt",0,"UInt",fattribs
                  ,"UInt",sharemode,"UInt",createdist,"UInt",flags,"UInt",0,"UInt",0, "UInt") 
  return % ExtractInteger(fh) 
} 


SetUnicodeStr(ByRef out, str_)
{ 
  VarSetCapacity(st1, 8, 0) 
  InsertInteger(0x530025, st1) 
  VarSetCapacity(out, (StrLen(str_)+1)*2, 0) 
  DllCall("wsprintfW", "str", out, "str", st1, "str", str_, "Cdecl UInt") 
} 


ExtractInteger(ByRef pSource, pOffset = 0, pIsSigned = false, pSize = 4) 
; pSource is a string (buffer) whose memory area contains a raw/binary integer at pOffset. 
; The caller should pass true for pSigned to interpret the result as signed vs. unsigned. 
; pSize is the size of PSource's integer in bytes (e.g. 4 bytes for a DWORD or Int). 
; pSource must be ByRef to avoid corruption during the formal-to-actual copying process 
; (since pSource might contain valid data beyond its first binary zero). 
{ 
  Loop %pSize%  ; Build the integer by adding up its bytes. 
    result += *(&pSource + pOffset + A_Index-1) << 8*(A_Index-1) 
  if (!pIsSigned OR pSize > 4 OR result < 0x80000000) 
    return result  ; Signed vs. unsigned doesn't matter in these cases. 
  ; Otherwise, convert the value (now known to be 32-bit) to its signed counterpart: 
  return -(0xFFFFFFFF - result + 1) 
} 


InsertInteger(pInteger, ByRef pDest, pOffset = 0, pSize = 4) 
; The caller must ensure that pDest has sufficient capacity.  To preserve any existing contents in pDest, 
; only pSize number of bytes starting at pOffset are altered in it. 
{ 
  Loop %pSize%  ; Copy each byte in the integer into the structure as raw binary data. 
    DllCall("RtlFillMemory", "UInt", &pDest + pOffset + A_Index-1, "UInt", 1, "UChar", pInteger >> 8*(A_Index-1) & 0xFF) 
}

 

[alan111]

So what does this do exactly?

While booted in Windows, this will enable the CAPS lock key LED to illuminate when the Air is on? Can't you just tell it's on by seeing the LCD is on?

 

[Penooker]

Yes, that's all it does.

If your LCD doesn't turn off while the laptop is on, then, yes, just look at the LCD.

 

[alan111]

Yes, that's all it does.

If your LCD doesn't turn off while the laptop is on, then, yes, just look at the LCD.

Will it blink slowly while it's in sleep mode? or will the LED just turn off while it's sleeping?

 

[Penooker]

It will be off. I wish it could blink slowly.

 

[alan111]

It will be off. I wish it could blink slowly.

So then I don't get the point of this. If the computer is on and the LCD is off, just tap a key on the keyboard or touch the touchpad to see if it's actually on. When you do that, won't it just wake up the computer and turn the LCD on?