Changes
Complete keyboard scanning routine slightly optimized
ld d,b ;1
out (c),c ;4
ld bc,#f792 ;3
out (c),c ;4
ld a,#40 ;2
ld c,#4a ;2 4443
loop ld b,d ;1
out (c),a ;4 select line
ld bc,#f782 ;3
out (c),c ;4
ei ;1 8 =211 210 microseconds
ret
</pre>
