Changes

Intel 8080

355 bytes removed, 27 February
/* Compatibility */
One important but subtle change was that the 8 register/memory codes were reordered to start with B instead of A. The motivation is that this gave registers in a 16-bit register pair (BC, DE, or HL) codes that differ only in the low bit. This makes it easier to specify a register pair with a two-bit code.
 
The 8080 ultimately led to the machine code-compatible, but more powerful clone Zilog [[Z80]], which was of course also used in the Amstrad [[CPC]] and Sinclair [[ZX Spectrum]] among others. (Note that 8080 assembly language looks different from Z80 mnemonics; e.g. the Z80 uses <tt>LD</tt> whereas the 8080 has <tt>MOV</tt> and several other commands.)
[[CP/M]] required an 8080, 8085 or Z80 CPU and between 1976 and about 1983, microcomputers with a Z80 that ran CP/M were the norm before the market shifted to MS-DOS.
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