??? That is, it
stores the least significant byte of a multiple byte value at the lower (first) address. So, the first byte of a 2-byte
address contains the low-order 8 bits, and the second byte contains the high-order 8 bits.
CHAP. 3] COMPUTER ORGANIZATION 37
An advantage of the little endian design is evident with the JMP instruction because the ???short??? version of
the JMP instruction takes only an 8-bit (1-byte) operand, which is naturally the low-order byte (the only byte).
So the JMP direct with a 2-byte operand simply adds the high-order byte to the low-order byte. To say this
another way, the value of the jump destination, whether 8 bits or 16 bits, can be read starting at the same address.
Other computers, such as the Sun SPARC, the PowerPC, the IBM 370 and the MIPS, are ???big endian,??? meaning
that the most significant byte is stored first. Some argue that big endian form is better because it reads more
easily when humans look at the bit pattern, because human speech is big endian (we say, ???four hundred, forty,???
not ???forty and four hundred???), and because the order of bits from least significant to most significant is the same
within a byte as the ordering of the bytes themselves.
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