Re: Cycle of Keyboard?

[Chris Beall <Chris_Beall@prodigy.net>]

Bryan Parkoff wrote:
> Hello,
>
>     In our old time when we had Apple II computer.  We know that 6502 CPU 
> must be involved to manipulate video, floppy drive, tape cassette, sound, 
> and more.
>     Do you believe that keyboard's repeating rate is from 6502 CPU's cycle 
> count rather than individual repeating rate inside keyboard?  I can't 
> remember what Understanding Apple //e book says that keyboard's repeating 
> rate is approximately 2 to 10Hz?  It can't be right because repeating letter 
> appearing in the screen is too fast.
>     Do you know someone who they write algorithm to manipulate repeating 
> rate individually without depending on Windows Message Loop such as 
> WM_KEYDOWN inside WinProc function?  Some programmers claim that it is 
> impossible, but they stick with Windows Message Loop.  It has to find other 
> way to track repeating rate accurately by counting 6502 CPU cycles.
>
> Bryan Parkoff 
Bryan,

On the Apple ][, the keyboard repeat is about 10Hz, controlled by a 555 
timer chip on the keyboard.  No 6502 cycles required.

Ref: Understanding the Apple ][, p. 7-13.

Chris Beall