simply by changing how many bytes in memory you choose to read while with Big Endian if you have 5461 stored as 2 bytes then you have 00010101 01010101 but if you have it stored as 4 bytes then you have 00000000 00000000 00010101 01010101, meaning to read it as 2 bytes you'd have to add 2 bytes to the address before you tried to read it with Little Endian the 4 byte version would be 01010101 00010101 00000000 00000000 so you don't have to add anything to read it as only 2 bytes (or 1, etc.).
The effect is that with Big Endian the most "significant" value is stored first while with Little Endian the "least" significant value is stored first and that with Little Endian you can easy read a value as 1 byte, 2 bytes, 4, 8, etc. If you had the value, say, 5461 which is 00010101 01010101 Big Endian says to store each byte exactly like that in memory with the 0001010 first followed by the 01010101 byte while Little Endian says to reverse the bytes and store 01010101 first followed by 00010101. The Big Endian difference comes in with multi-byte values like 2 byte and 4 byte. If you aren't supporting negative numbers, aka the value is "unsigned", then the minimum value is 00000000, or 0, max value is 11111111, or 255 (0xFF in hexadecimal). A "byte" is made up of 8 of these binary digits, aka bits. 21 is 2 * 10 ^ 1 + 1 * 10 ^ 0 = 2 * 10 + 1) in binary each place value is multiplied by 2 to the power of the place so 10 is 1 2 1 + 02 0 = 2 + 0 = 2. Like decimal where each place value is multiplied by 10 to the power of the place -1 (eg. The binary number system has only 2 possible values for a digit, represented with 0 or 1 rather like decimal has 10, 0,1,2,3,4,5,6,7,8,9 and hexadecimal has 16 0-9 plus A,B,C,D,E,F. To explain that you really need at least a basic understanding of how binary numbers work. Some of the hardware used the "Big Endian" storage format rather than the "Little Endian" method like Windows.They often use memory mapping which CE doesn't scan by default (go to the "Scan Settings" section of CE's settings).This is why you need an emulator in the first place instead a regular program with "levels" or "maps" for different games. They often aren't running entirely x86/圆4 code, they're "emulating" a different CPU type like ARM which uses different values for instructions which work in different ways from how your CPU works.
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