Changes

Programming:Keyboard scanning

11 bytes added, 28 March
/* Complete keyboard scanning routine */
out (c),c ;4
ld a,#40 ;2
ld c,#4a d ;2 431 (+42)
loop ld b,d ;1
out (c),a ;4 select line
ini ;5 read bits and write into KEYMAP
inc a ;1
cp inc c ;1 jr cnz,loop ;2/3 (9*16+1*15=159)
ld bc,#f782 ;3
out (c),c ;4
ei ;1 (+8 =210 209 microseconds)
ret
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