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A comment on Bill Gates: “I never said '640K should be enough for anybody'” (1996). Parent comment

Re:Bill Gates: “I never said '640K should be enough for anyb... by unilynx on Tuesday October 02, 2018 @12:46PM (#18123330)
The 8086/8088 didn't have that A20 line setting. That was added later for backwards compatibility.

The 80286 reset thing wasn't a full PC reset, but a CPU reset.

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Re:Bill Gates: “I never said '640K should be enough for anyb... by vetinari on Tuesday October 02, 2018 @01:39PM (#18123870)
> The 8086/8088 didn't have that A20 line setting. That was added later for backwards compatibility.

True

> The 80286 reset thing wasn't a full PC reset, but a CPU reset.

That required an extra hardware and BIOS support. The CPU had to be reset externally, and after jumping to FFFF:0000, the BIOS had to recognize that this is a CPU reset, not re-initialize the hardware and return execution to where it came from.

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