keyboard repeat delay, can this be set by VB to 0?

[MadLabs]

Hi All,

I am using the Form_Keypress function to capture keystrokes and send them out via the serial port. I want to set the repeat delay to 0. You know how when typing in a word processor program when you hold a key down, the character appears on the screen, there is a short delay, then the charcter begins to repeat across the screen. Using the control panel of the computer, I can set it pretty low, but I want no delay at all.

What I am doing is controlling a robot with the keyboard, so the initial repeat delay causes a stutter in the robot's motion. If there was no repeat delay, no stutter. I've looked, but I can't see a way to set that.

Thanks,

Jonathan

www.madlabs.info

[Dave Sell]

Try This:

' #VBIDEUtils#*****************************************
' * Programmer Name  : Waty Thierry
' * Web Site   : [url]http://www.geocities.com/ResearchTriangle/6311/[/url]
' * E-Mail     : [email][email protected][/email]
' * Date       : 25/11/1999
' * Time       : 15:59
' *************************************************************
' * Comments   : Change the keyboard speed and the repeat delay
' *
' ********************************************************
Private Declare Function SystemParametersInfo Lib "user32" _
  Alias "SystemParametersInfoA" (ByVal uAction As Long, _
   ByVal uParam As Long, ByVal lpvParam As Any, _
   ByVal fuWinIni As Long) As Long
 
Private Const SPI_SETKEYBOARDDELAY = 23
Private Const SPI_SETKEYBOARDSPEED = 11
Private Const SPIF_SENDCHANGE = 1

And:

Public Function SetKeyBoardSpeed(NewSpeed As Long) As Boolean
 
'PASS A NUMBER BETWEEN 0 AND 31
'31 IS THE FASTEST SPEED
'0 IS THE SLOWEST
 
   Dim Retcode As Long
   Dim dummy As Long
 
   Retcode = SystemParametersInfo(SPI_SETKEYBOARDSPEED, _
      NewSpeed, dummy, SPIF_SENDCHANGE)
 
  SetKeyBoardSpeed = (Retcode > 0)
End Function
 
Public Function SetKeyBoardDelay(NewDelay As Long) As Boolean
'PASS A VALUE BETEEN 0 AND 3.  0 for the SHORTEST DELAY
'(ABOUT 250 ms) 3 for the longset (ABOUT 1 sec)
 
   Dim Retcode As Long
   Dim dummy As Long
   dummy = 0
    
     Retcode = SystemParametersInfo(SPI_SETKEYBOARDDELAY, _
         NewDelay, dummy, SPIIF_SENDCHANGE)
 
      SetKeyBoardDelay = (Retcode > 0)
End Function

Found here:

http://www.freevbcode.com/ShowCode.asp?ID=511

[MadLabs]

Dave,

Thanks! I'm having a little trouble getting it to work, but I'm sure I can. My question is, is 250mS any faster than can be set by the computer's control panel? At a guess, I'd say no. Have any idea if that is true?

Thanks again,

Jonathan

www.madlabs.info

[Dave Sell]

<Star Trek>

Sorry Captain, that's as much as I can give yer! She'll buckle if we take 'er any faster!

</Star Trek>

Basically those are IEEE standard settings that cannot be changed.

[MadLabs]

<Star Trek>

Scotty, divert everything but life support to the warp drive! I *MUST* have more power!

But Sir!! I dinna know how much longer she'll take! The dilithium cyrstals are going to blow!

</ Star Trek>

Dang. Guess what I will have to do is somehow intercept the keystroke and do some sort of loop to send out the commands. There has to be a way around this. I will break the 250mS barrier!

Thanks for all the help, dave

Jonathan

www.madlabs.info

[Dave Sell]

<Star Trek>

Sir! Ye moost be crazy to think ye cun take 'er to sooch extremes!! I cannot keep 'er together mooch longer!!! Take a step back from yer captain's chair and think about what yer doin!

</Star Trek>

Yes, it is time to "refactor" your program. I am assuming you sent a command everytime the key_Press event was fired, which you can only get to occur every 250 ms.

I wrote a keyboard handler once in assembly, but I think you can do it in VB also.

If you want to try something new:

- In the KeyDown event, set some global variable to represent the command you want to send.

- Have a timer object fire at maximum frequency (adjustable)

- Every time the timer event gets fired, check and send the command matching the global variable that was set in the KeyDown event

- *important* in the KeyUP event, RESET the global command to not send any commands

Let me know how that works if you try it.