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

[Bob Weigel]

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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