righto.com has been great reading. None of my friends wanted to pay for an 8087, but I can still remember getting out of school (for 2nd time) and saving up for the 486DX after 3 others got them. After that, well, it's been quite a ride.
There's a ton of coordination lately on P6 microcode. Would love to see what twists and turns there are supporting the older isa on newer architectures
righto.com has been great reading. None of my friends wanted to pay for an 8087, but I can still remember getting out of school (for 2nd time) and saving up for the 486DX after 3 others got them. After that, well, it's been quite a ride.
Minor erratum: "1.1 (binary) × 2^8 is 304" should be 384.
Thanks! I guess I didn't have my glasses on when I read that number :-)
There's a ton of coordination lately on P6 microcode. Would love to see what twists and turns there are supporting the older isa on newer architectures
Have you already covered how the decoding of instructions is shared with the 8086?
I describe the 8087 instruction decoding here: https://www.righto.com/2026/02/8087-instruction-decoding.htm...
How do FSTSW AX and similar instructions write to AX?
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I am curious about the transcendental instructions, how are they implemented, and used, and if actually used
https://www.righto.com/2026/09/8087-tangent-cordic.html
They definitely were used back in the day, now the x87 isn't used much at all.
If your look at {whatever part is next} is this interesting, I don't know if "which one?" really matters much.