1. Byte Addressability Bytes are always 8 bits Word length typically ranges from 16 to 64 bits. Memory location assignments refer to successive byte locations in memory Memory is byte-accessible. For 8086, a Word is 16-bits (2 bytes)

2. Word Length For the 8086, a Word is 16-bits (2 bytes) A Signed Integer b 15 b 14 …………b1b1 b0b0 2 Characters 8 bits

3. Little-Endian Formatting There are two ways that byte addresses can be assigned across words. –Big-Endian – higher byte addresses are used for the less significant bytes of a word –Little-Endian – lower byte addresses are used for the less significant bytes of a word –The Intel Architecture uses Little Endian

4. Little-Endian Assignments.data List BYTE 10, 20, 30, 40, 50, 60 OffsetValue 000560 000450 000340 000230 000120 000010 *note that with byte size data, there is no difference between Big-Endian and Little-Endian

5. Big-Endian Assignments.data List BYTE 10, 20, 30, 40, 50, 60 OffsetValue 000560 000450 000340 000230 000120 000010 *note that with byte size data, there is no difference between Big-Endian and Little-Endian

6. Little-Endian Assignments.data List WORD 1020h, 3040h, 5060h OffsetValue 000550 000460 000330 000240 000110 000020 *note that with word size data, the low-order byte is stored in a lower address

7. Big-Endian Assignments.data List WORD 1020h, 3040h, 5060h OffsetValue 000560 000450 000340 000230 000120 000010 *note that with word size data, the low-order byte is stored in a higher address

8. Little-Endian Assignments.data List DWORD 10203040h, 50607080h OffsetValue 000570 000480 000310 000220 000130 000040 *note that with word size data, the low-order byte is stored in a lower address

9. Big-Endian Assignments.data List DWORD 10203040h, 50607080h OffsetValue 000560 000450 000340 000230 000120 000010 *note that with word size data, the low-order byte is stored in a higher address

10. Big-Endian Assignments.data List DWORD 00000006h OffsetValue 0005XX 0004 XX 0003 06 0002 00 000100 000000 *note that with word size data, the low-order byte is stored in a higher address

11. Little-Endian Assignments.data List DWORD 00000006h OffsetValue 0005XX 0004 XX 0003 00 0002 00 000100 000006 *note that with word size data, the low-order byte is stored in a higher address

12. Big-Endian Assignments.data List BYTE “This is a string”,0 OffsetValue 0005 73 0004 20 0003 73 0002 69 0001 68 000054 *note: These are the ASCII values ‘T’=54H, ‘h’=68H, ‘ i’= 69H …

13. Little-Endian Assignments.data List BYTE “This is a string”,0 OffsetValue 0005 73 0004 20 0003 73 0002 69 0001 68 000054 *note: Strings are saved as byte data