Hacker News: pechay

New comment by pechay in "Microcode in Intel's 8087 floating-point chip: the scale instruction"

pechay — Sat, 12 Sep 2026 18:57:57 +0000

Great work! I love to read your articles.

I'm curious to know - you say Intel's 8087 emulation code was a bit of a lump at 16KB, do you know if it emulated the 8087 microcode state machine or did it use a different strategy?

New comment by pechay in "Writing a (valid) C program without main()"

pechay — Sat, 25 Jul 2026 17:08:35 +0000

All C programs are interesting. The first potentially non-interesting program in C is interesting because it's the first non-interesting one. :)

New comment by pechay in "A brief history of threads and threading"

pechay — Sun, 21 Sep 2025 11:01:46 +0000

It's worth pointing out the Commodore Amiga had proper pre-emptive multitasking on a single M68000 all the way back in July '85

New comment by pechay in "Show HN: I recovered one of my earliest ZX-Spectrum games from an audio cassette"

pechay — Sat, 25 Jan 2025 16:53:24 +0000

Thank you for your incredibly detailed correction :)

New comment by pechay in "Show HN: I recovered one of my earliest ZX-Spectrum games from an audio cassette"

pechay — Sat, 25 Jan 2025 10:50:50 +0000

The ZX Spectrum ROM loader is 1500bps and some games loaded at over 3000. There wasn't any encoding, just straight-up 1s and 0s straight into RAM.

New comment by pechay in "Reciprocal Approximation with 1 Subtraction"

pechay — Tue, 31 Dec 2024 23:02:44 +0000

The 68k has both signed and unsigned 32/16 bit divide instructions.

New comment by pechay in "In 1870, Lord Rayleigh used oil and water to calculate the size of molecules"

pechay — Mon, 23 Sep 2024 23:26:39 +0000

We did this same experiment in school, with a tiny pinprick of oil, estimating the volume of the drop as a sphere, and a small water tank, and then estimated the area of oil slick as a circle.

New comment by pechay in "Qubit Transistors Reach Error Correction Benchmark"

pechay — Thu, 12 Sep 2024 14:18:12 +0000

University of New South Whales!

New comment by pechay in "Ford F-150 Lightnings will soon offer home AC power, possibly cheaper than grid"

pechay — Sat, 09 Dec 2023 06:03:15 +0000

If everyone starts using cheap off-peak power, will it continue to be cheap?

New comment by pechay in "Amiga Graphics Archive"

pechay — Tue, 28 Nov 2023 16:26:00 +0000

The Amiga didn't have any hardware assistance for scaling sprites, so almost certainly the former.

New comment by pechay in "Linear code is more readable"

pechay — Fri, 15 Sep 2023 21:05:00 +0000

pizza isn't, and can't be, opaquely modified by the topping adder this way.

New comment by pechay in "Linear code is more readable"

pechay — Fri, 15 Sep 2023 04:53:46 +0000

I don't like the side effects of the second addToppings. I'd much prefer

pizza.Toppings = getToppings(kind string)

New comment by pechay in "Living in Airbnbs full time isn’t easy (2021)"

pechay — Mon, 12 Jun 2023 08:12:42 +0000

I've stayed in over fifty Airbnb in the last three years. Only three haven't worked out (misleading apartment, mouse-poop kitchen, unresponsive host). Each time Airbnb has sorted me out with a refund, called me to discuss the problem, helped finding an alternative place, and providing a voucher to cover any price gap.

New comment by pechay in "Ask HN: Did Anyone Else Here Simply Not Do Well at School?"

pechay — Sat, 03 Jun 2023 16:17:58 +0000

If you're certain it's what you want, don't accept no for an answer and keep hassling the school or college at different levels and see if you can still make it happen.

New comment by pechay in "Why Self-Checkout Is and Has Always Been the Worst"

pechay — Wed, 17 May 2023 16:17:05 +0000

Do you ever buy alcohol?

New comment by pechay in "Retro Computer Museum"

pechay — Wed, 17 May 2023 13:27:25 +0000

The RCM is fantastic, definitely worth a visit, and Andy who runs the place is a legend.

New comment by pechay in "Merge branch 'x86-rep-insns': x86 user copy clarifications"

pechay — Tue, 16 May 2023 11:13:15 +0000

I think unrolled FILD/FIST was fastest on Pentium.

New comment by pechay in "Ask HN: What is the best product documentation you’ve ever seen?"

pechay — Sat, 06 May 2023 14:40:43 +0000

Similarly, the manual that came with the original ZX Spectrum rubber key version was awesome, with a complete description of Sinclair BASIC and all the Z80 assembler op codes for good luck. The 48k+ manual that followed was nowhere near as useful.

New comment by pechay in "A SVB short seller explains red flags he saw months ago"

pechay — Sat, 11 Mar 2023 16:48:03 +0000

Disable JavaScript also works.

New comment by pechay in "Ask HN: How to negotiate shares at my new job?"

pechay — Fri, 23 Dec 2022 15:34:20 +0000

Make sure you are paid and bonused properly regardless of any future exit, because most startups never get there. In CTO role you should get something at the exit too, because you are likely to be instrumental in that success. Because companies often pivot or your part of the company changes outside of your control, you should have both.