[sdiy] lovely 'glitch' puzzle...siel DK600 74HC923 key matrix read

[Barry Klein]

Maybe shooting it is a good approach - shotgun approach: replace the hc244(s) related to the panel interface.

Sent from my iPad

On Dec 28, 2011, at 2:54 AM, Bob Weigel <sounddoctorin at imt.net> wrote:

> wow... it's like it totally fooled me into thinking it was ok then reverted back again.  Cleaned the board..no result.
> 
> THIS IS WILD though listen to this
> 
> 1) all the outer buttons are never affected.  Eg. the modulation buttons.  The upper two to the right.... and then all four on the far right.
> 
> 2) The footage buttons also seem to never be affected though..I thought they were before. hmm
> 
> 3) Every other button may be altered randomly though the pwm button seems to rarely impact other things unless there is some other 'history...
> 
> 4) the programmer section though it's on a different chip entirely... will affect the SAME ONES that get affected by buttons on the other side!!  Yet the display on the programmer is never affected (Save the cursor led which is supposed to blink whenever stuff is changed)
> 
> the only common element here is the interrupt line which merges from the two Data Available lines from the 923 chips!!
> 
> Wow.  What a weird one.  I'm ready to shoot it.  Dug into the PE1000 I got in today that got scantly packed yet somehow survived.  Yet way more problems than represented.  joy.
> 
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