Pull out the plastic bit, the cable should pull out easily then
Thanks, that worked.
Needed a lot of persuasion though. Not looking forward to removing display
Ah.... now I get it
just flip the black plastic up like a piano lid - much easier and less destructive
So, starting off with the simplest task:
Left hand keypad keys top to bottom are: K5 K12 K13 K11 K9 K2 K4 K3 K1
Left hand keypad ribbon cable listed top=1 to bottom = 8:
ribbon 1 = K5 R , K1 L , K2 L , K3 L , K4 L
ribbon 2 =K9 L , K11 L , K12 L , K13 L
ribbon 3 = K5 L , K13 R
ribbon 4 = ground to button PCB ground
ribbon 5 = K4 R, K12 R
ribbon 6 = K3 R , K11 R
ribbon 7 = K2 R
ribbon 8 = K1 R , K9 R
I make that a 2x5 matrix with:
ribbon 1 = row 1 (K1 to K5)
ribbon 2 = row 2 (K9 to K13) K10 not fitted
ribbon 3 = column 5 (K5 K13)
ribbon 4 gnd
ribbon 5 = column 4 (K4 K12)
ribbon 6 = column 3 (K3 K11)
ribbon 7 = column 2 (K2)
ribbon 8 = column 1 (K1 K9)
Dave's teardown seems to suggest that the 8 way side-connector is related to the 8-way key connector nearby, but continuity test shows that the two are not directly connected. My guess is that the positioning is co-incidence.
On to the other keyboard panel with all of the rotary encoders on. I see that there is an ASIC hidden away behind the board, so this board more complex than I first guessed.
EDIT: Turns out the two keyboards work as one 6x8 matrix - where row 6 has K41 button (CH4) plus K54 through K59 which are the push function of the rotary switches