CompuServe Messages

>> but if you write your program for the 8086, it will be very inefficient >> compared to the same program coded directly for the 486 Hmm.. could you be a little more concrete ? .. Well, the 486 has registers that make copying to/from memory blocks and stuff a lot easier, rather than just increasing the speed of their processor, which was originally 8 bit, in order to get up to 32 bit modes Intel had to make new instructions to fully take advantage of 32 bits. The 68000 can add and subtract 32 bit words. and the 68020 can multiply and divide 32 and even 64 bit quantities. The 8086 operates on 8 bits. So if you want to do 32 bit operations, you are using 286, 386, or 486 specific instructions – your code will not work on a 8088/8086. If you were to program right out of the 8086 hardware ref manual, your program would be inefficient compared to using 386 instructions.