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Created page with "= Next line = This routines calculate the next line from the given address. == Firmware == '''Input:''' HL=Address '''Output:''' HL=Address of the next line '''Destroyed:'''..."
= Next line =
This routines calculate the next line from the given address.
== Firmware ==
'''Input:''' HL=Address
'''Output:''' HL=Address of the next line
'''Destroyed:''' AF
<pre>
SCR_NEXT_LINE equ #BC26
call SCR_NEXT_LINE
</pre>
== Without Firmware ==
'''Input:''' HL=Address
'''Output:''' HL=Address of the next line
'''Destroyed:''' AF
<pre>
; Richard Fairhurst
; October 1997
;
;*** Next line down from HL ***
.nline ld a,8
add h
ld h,a
and 64
ret nz
ld bc,16304
sbc hl,bc
ret
</pre>
= Previous line =
This routines calculate the previous line from the given address.
== Firmware ==
'''Input:''' HL=Address
'''Output:''' HL=Address of the previous line
'''Destroyed:''' AF
<pre>
SCR_PREV_LINE equ #BC29
call SCR_PREV_LINE
</pre>
[[Category:Programming]]
This routines calculate the next line from the given address.
== Firmware ==
'''Input:''' HL=Address
'''Output:''' HL=Address of the next line
'''Destroyed:''' AF
<pre>
SCR_NEXT_LINE equ #BC26
call SCR_NEXT_LINE
</pre>
== Without Firmware ==
'''Input:''' HL=Address
'''Output:''' HL=Address of the next line
'''Destroyed:''' AF
<pre>
; Richard Fairhurst
; October 1997
;
;*** Next line down from HL ***
.nline ld a,8
add h
ld h,a
and 64
ret nz
ld bc,16304
sbc hl,bc
ret
</pre>
= Previous line =
This routines calculate the previous line from the given address.
== Firmware ==
'''Input:''' HL=Address
'''Output:''' HL=Address of the previous line
'''Destroyed:''' AF
<pre>
SCR_PREV_LINE equ #BC29
call SCR_PREV_LINE
</pre>
[[Category:Programming]]
