The custom rom option says 64K is that the maximum size ?
Can i just load an 8k rom image or do i have to make it 64K ?
Happy New Year
.ORG $0000
DI
CALL settxtmode
ld h,20 ;X cursor value
ld l,20 ;Y cursor value
call xy2txt_addr
ld (hl),$41 ;Character A - 65
HALT
settxtmode
ld a,1 ;set shadow mode
out ($BF),a
ld bc,$ff77 ;set txt mode
ld a,$26
out (c),a
ld a,5^$ff ;set 5_ram_page to 1 bank z80
ld bc,$77f7
out (c),a
ld a,1^$ff ;set 1_ram_page to 2 bank z80
ld b,$b7
out (c),a
xor a ;close shadow ports
out ($BF),a
ret
xy2txt_addr ;input h=x l=y symbol
ld a,$07 ;output hl=address
srl h
jr nc,l1
ld a,$87
l1 add a,l
ld l,h
ld h,a
xor a
srl h
rr a
srl h
rr a
add a,l
ld l,a
set 6,h
ret
xy2attr_addr ;input h=x l=y symbol
ld a,$87 ;output hl=address
srl h
jr nc,l2
ld a,$07
inc h
l2 add a,l
ld l,h
ld h,a
xor a
srl h
rr a
srl h
rr a
add a,l
ld l,a
set 7,h
ret
TXT2ATTR ;input hl=txt_symb address
ld a,%11100000 ;output hl=attr_symb address
xor h
ld h,a
bit 5,h
ret nz
inc hl
ret
; Fill rest of rom with $FF upto $FFFF
.FILL $10000-$,$FF
.END
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