Sharp MZ-700 - Page 144

[Keyboard matrix circuit]
8255 outputs keyboard scan signals from port PA to the keyboard and reads key data from port PB.
The figure below snows the key matrix .
...
0
0
w
~
ell
....
~ 15 t-:0---f------i
~ 3
~
Keyboard connector L E 0
l
~®®@®®0®®®®®®@®@®@@@
i
GNO
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