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Ball In A Box Productions
; *** Iterate through all non unique byte values ; *** less than 254 of any quantity ; *** buffer multple of 4 and zero terminated byteOdom proc STDCALL buff:DWORD,qty:DWORD,range:DWORD push edi ; push edi onto the stack mov edi,buff ; address of odomoeter values mov edx,256 ; highest byte value+1 sub edx,range ; byte range n to 255 mov ecx,qty ; number of bytes in odometer lp00: mov [edi+ecx-1],dl ; initialize one byte in buffer loop lp00 ; decement ecx and loop till zero dec byte ptr [edi] ; start with -1 for first iteration next: sub ebx,ebx ; zero a forward dword offset lp01: mov eax,ebx ; working dword offset inc ebx ; point to next dword inc dword ptr [edi+eax*4] ; increment dword je lp01 ; loop if these 4 expired to zero sub ebx,ebx ; byte offset forward pointer lp02: mov eax,ebx ; working byte offset pointer inc ebx ; point to next byte cmp [edi+eax],dl ; compare byte to lowest byte value jc notOk ; jump if byte not within valid range ; *** odometer values incremented and correct mov eax,[edi] ; get least significant odometer byte sub eax,edx ; normalize to get the value nop ; action to be taken jmp next ; loop and increment the odometer notOk: cmp byte ptr [edi+eax],0 ; compare byte to zero mov byte ptr [edi+eax],dl ; reset byte to lowest value je lp02 ; loop and check next byte pop edi ret byteOdom endppseudocode
let lowValue = 256 - odometer range
fill an array of quantity elements with lowValue
do
do
increment 4 array elements little endian with carry
point to next 4 array elements
loop while incremented elements all equal zero
for each element in array
if element = 0
element = lowValue
end if
loop while element > 1
if element > 1
value = array[0 to odometer range] - lowValue
rem action to be taken
endif
while element > 1
fill an array of quantity elements with lowValue
do
do
increment 4 array elements little endian with carry
point to next 4 array elements
loop while incremented elements all equal zero
for each element in array
if element = 0
element = lowValue
end if
loop while element > 1
if element > 1
value = array[0 to odometer range] - lowValue
rem action to be taken
endif
while element > 1
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