static int memcmp_mask(const void *ptr1, const void *ptr2, const void *mask, size_t len)
{
    const uint8_t *p1 = (const uint8_t*)ptr1;
    const uint8_t *p2 = (const uint8_t*)ptr2;
    const uint8_t *m = (const uint8_t*)mask;

    while(len--)
    {
        int diff = m?(*p2 & *m)-(*p1 & *m):*p2-*p1;
        if (diff) return diff>0?1:-1;
        p1++;
        p2++;
        if (m) m++;
    }
    return 0;
}

needle = E6 F4 00 00 E6 F5 00 00 DA 00 D8 7E
  mask = ff ff 00 00 ff ff 00 00 ff ff ff ff

    //                            LL    LL                HH
    uint8_t n0[] = {0xE6, 0xF8, 0x00, 0x00, 0xE6, 0xF9, 0x00, 0x00, 0xF2, 0xF4, 0x00, 0x00, 0x24, 0x8F};
    uint8_t m0[] = {0xff, 0xff, 0x00, 0x00, 0xff, 0xff, 0x00, 0xff, 0xff, 0xff, 0x00, 0x00, 0xff, 0xff};
    //                                        LL    LL                HH
    uint8_t n1[] = {0x10, 0x9B, 0xE6, 0xF4, 0x00, 0x00, 0xE6, 0xF5, 0x00, 0x00, 0x26, 0xF4};
    uint8_t m1[] = {0xff, 0xff, 0xff, 0xff, 0x00, 0x00, 0xff, 0xff, 0x00, 0xff, 0xff, 0xff};

Step #1: Reading main ROM CRC...
Searching for main ROM CRC block starts...
Found possible CRC block starts #1 at 0x810002 (from 0x9029e)
Found possible CRC block starts #2 at 0x814252 (from 0x90318)
Found possible CRC block starts #3 at 0x818192 (from 0x90392)
Found possible CRC block starts #4 at 0x826a00 (from 0x90410)
Too many matches (4). CRC block start find failed
Searching for main ROM CRC block ends...
Found possible CRC block end #1 at 0x813ffe (from 0x902c0)
Found possible CRC block end #2 at 0x817f4e (from 0x9033a)
Found possible CRC block end #3 at 0x81fbdc (from 0x903b4)
Found possible CRC block end #4 at 0x82fffc (from 0x90432)
Too many matches (4). CRC block end find failed
Searching for main ROM CRC offsets...
Found possible CRC offset #1 at 0x890000 (from 0x904a2)
Found possible CRC offset #2 at 0x890006 (from 0x90522)
Found possible CRC offset #3 at 0x89000c (from 0x905aa)
Found CRC #1 at 0x890000
Found CRC #2 at 0x890006
Found CRC #3 at 0x89000c

Adr: 0x810002-0x813FFE @0x90000 CRC: 0x13BFD815  CalcCRC: 0xA13F9F2B  ** NOT OK **
Adr: 0x814252-0x817F4E @0x90006 CRC: 0x8C92421A  CalcCRC: 0xC52D9DB4  ** NOT OK **

_InitMultipoint: 
		mov	initvar1, ZEROS                                    ; {F6} 8E, {FA 80}  offset+x80fa
		mov	initvar2, ZEROS                                    ; {F6} 8E, {FC 80}  offset+x80fc
		movb	initvar3, ZEROS                                    ; {F7} 8E, {03 81}  offset+x0381

		extp	#518, #2                                            ; {D7} 50 06 02
		mov	r4, MainRom_Checksum_START_Low        ; {F2} F4,{ E6 3F } offset+x3fe6 [file offset=x6b982]
		mov	r5, MainRom_Checksum_START_High        ; {F2} F5,{ E8 3F } offset+x3fe8 [file offset=x6b986]

		mov	MainRom_Checksum_START_Low_cpy, r4  ; {F6} F4,{ FE 80 } offset+x80fe [file offset=x6b98a]
		mov	MainRom_Checksum_START_High_cpy, r5  ; {F6} F5,{ 00 81 } offset+x8100 [file offset=x6b98e]

		movb	rl4, #1                                                ; {E1} 18
		movb	loop_counter, rl4                                  ; {F7} F8 { 02 81 } offset+x8102
		extp	#518, #2                                            ; {D7} 50 { 06 02 } ;x0206 == 518 decimal

		mov	r4, MainRom_Checksum_END_Low            ; {F2} F4 { EA 3F } offset+x3fea [file offset=x6b99c]
		mov	r5, MainRom_Checksum_END_High            ; {F2} F5 { EC 3F } offset+x3fec [file offset=x6b9a0]

		mov	MainRom_Checksum_End_Low_Cpy, r4      ; {F6} F4 { 04 81 } offset+x8104
		mov	MainRom_Checksum_End_High_Cpy, r5      ; {F6} F5 { 06 81 } offset+x8106

		rets                                    ; {DB 00}