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About 1981, intel manufactured the 8086 processor that had been choosed
by IBM for its new computer, who would thought that we would depend so
much of this architecture.
The 8086 is a 16 bits processor, that means that
internally it can work with numbers from 0 to 65535, the memory
addresses are 20 bits long that enables us to use up to one Mb for RAM.
The 8088 it's a variation of the first one, it's
single difference is that the data bus is 8 bits long instead of 16 .
It causes to write and read data using to steps. This processors are
the core for the called PC XT, that usually comes with: graphics card:
Hercules/CGA, some 8 bits ISA slots, one or two serial ports and a
parallel, one or two 5 ? floppy disk drives for 360Kb disks (double
side, double density) and maybe a hard disk drive 10 or 20 Mb.
The processors can run 92 different commands and
have got 7 addressing modes, its speed is 4.7 Mhz. Or 8Mhz. Also
there is the 8087 and we call it mathematic coprocessor or floating
point processor, if we plug it on the main board, and the software
supports it, will help vastly on computations. There is an interesting
thing to know on this processors is that there are 2 NEC processors
that could substitute it to gain performance.
Specifically the 8086 could be substituted for
NEC-V30, and 8088 for NEC-V20, in both cases there are absolutely
compatibles as in hardware as in software, they are processors who have
been optimised, and in certain commands overcomes till 3 times the
performance on its execution, also incorporates the additional 286
instructions in real mode.
Then if you'd have a super-XT at home, the best for
speed power is to substitute the processor by an NEC and to incorporate
a 8087 mathematic coprocessor. If we talk about RAM memory, could be
one Mb, but the usually is to find configurations with maximun
640Kb, where no problems will be reported for any software, you could
see it in the mainboard . If it has free space for more memory chips,
you have it and you know what jumper or switch you have to activate for
telling system how many memory it have, you could try it.