Hacker News: Taniwha

New comment by Taniwha in "Ternary Bonsai: Top Intelligence at 1.58 Bits"

Taniwha — Tue, 21 Apr 2026 03:24:56 +0000

and so you can at 1-bit too, and the hardware will be even smaller and cheaper

New comment by Taniwha in "Focused microwaves allow 3D printers to fuse circuits onto almost anything"

Taniwha — Mon, 20 Apr 2026 11:25:45 +0000

If you can print small enough with this technology I'm pretty sure you can make transistors - sort of 1980 era transistors, not very dense, but if you are printing bulk materials you can build in 3D rather than 2D, make interesting numbers of transistors, cpus in everything!

New comment by Taniwha in "Floating point from scratch: Hard Mode"

Taniwha — Wed, 08 Apr 2026 06:03:13 +0000

Wearing my chip designer's hat decimal FP just means more (and slower) gates

New comment by Taniwha in "Book review: There Is No Antimemetics Division"

Taniwha — Wed, 08 Apr 2026 06:01:15 +0000

If you like unreliable narration and rug pulls Nick Harkaway's novel 'The Gone-Away World' really takes the cake (and is brilliant)

New comment by Taniwha in "Floating point from scratch: Hard Mode"

Taniwha — Tue, 07 Apr 2026 11:06:13 +0000

Everyone who has ever had to build a floating point unit has hated it with a passion, I've watched in done from afar, and done it myself

New comment by Taniwha in "VHDL's Crown Jewel"

Taniwha — Mon, 30 Mar 2026 23:45:32 +0000

BTW my really big peeve about modern verilog is that it never picked up {/} as synonyms for begin/end - my experiments (20 years ago) showed that it was an easy extension, the minor syntactic ambiguities were trivally fixable

New comment by Taniwha in "VHDL's Crown Jewel"

Taniwha — Mon, 30 Mar 2026 07:41:17 +0000

I'm a long time verilog user (30+ years, a dozen or so tapeouts), even written a couple of compilers so I'm intimate with the gory details of event scheduling.

Used to be in the early days that some people depended on how the original verilog interpreter ordered events, it was a silly thing (models would only run on one simulator, cause of lots of angst).

'<=' assignment fixed a lot of these problems, using it correctly means that you can model synchronous logic without caring about event ordering (at the cost of an extra copy and an extra event which can be mostly optimised away by a compiler).

In combination 'always @(*)' and '=', and assign give you reliable combinatorial logic.

In real world logic a lot of event ordering is non deterministic - one signal can appear before/after another depending on temperature all in all it's best not to design depending it if you possibly can, do it right and you don't care about event ordering, let your combinatorial circuits waggle around as their inputs change and catch the result in flops synchronously.

IMHO Verilog's main problems are that it: a) mixes flops and wires in a confusing way, and b) if you stay away from the synthesisable subset lets you do things that do depend on event ordering that can get you into trouble (but you need that sometimes to build test benches)

New comment by Taniwha in "Alpha Micro AM-1000E and AM-1200"

Taniwha — Mon, 23 Mar 2026 02:34:17 +0000

yeah, that's rather a pain though and it effectively leaves one 68k frozen while the other services the page fault - it means you can't run another user process while the page is being read in (because it too might cause a page fault)

New comment by Taniwha in "Alpha Micro AM-1000E and AM-1200"

Taniwha — Sun, 22 Mar 2026 08:30:02 +0000

68451 or a custom SUN-like (SRAM, kind of like a PDP11) MMU, there was a guy who went around Silicon Valley in the mid 80s designing SUN-like MMUs for companies, they were all different, and some were broken (couldn't protect user space from kernel space).

68000s however had a problem: they couldn't return correctly from a page (MMU) fault (68010s fixed that) for a pre-VM (pre BSD or SVR2) UNIX world - however you could get around this with a few smarts

New comment by Taniwha in "Write up of my homebrew CPU build"

Taniwha — Wed, 18 Mar 2026 11:04:30 +0000

Of course while you're doing the next version you should knock out a tiny tapeout version, it should easily fit in a single cell (maybe 2 if you want to push the 256 byte sram in as well)

New comment by Taniwha in "Chiplets Get Physical: The Days of Mix-and-Match Silicon Draw Nigh"

Taniwha — Tue, 17 Feb 2026 01:11:38 +0000

I think that what we're all waiting for for this to take off is one of the Cheap Chinese assembly houses to set up a web site where you can drag and drop chiplets into a carrier with standard interface buses, you press a button and brrr-zap robots pull chiplet die onto a substrate, bond out the interfaces and ship you a prototype same day - because you all know this is totally the future

New comment by Taniwha in "The Singularity will occur on a Tuesday"

Taniwha — Tue, 10 Feb 2026 22:54:15 +0000

I was at an alternative type computer unconference and someone has organised a talk about the singularity, it was in a secondary school classroom and as evening fell in a room full of geeks no one could figure out how to turn on the lights .... we concluded that the singularity probably wasn't going to happen

New comment by Taniwha in "A few CPU hardware bugs"

Taniwha — Fri, 06 Feb 2026 02:33:51 +0000

I think FP needs it's own custom tests (billions of them!) - I hate building FP units, they are really the pits

New comment by Taniwha in "A few CPU hardware bugs"

Taniwha — Thu, 05 Feb 2026 09:57:55 +0000

This sort of bug, especially in and around pipelines are always hard to find. In chips I've built we've had one guy who built a system that would build random instruction streams to try and trigger as many as we possibly could

New comment by Taniwha in "1 kilobyte is precisely 1000 bytes?"

Taniwha — Tue, 03 Feb 2026 19:52:59 +0000

Oh sure, and next you'll say a byte is 10 bits ....

New comment by Taniwha in "The TSA's New $45 Fee to Fly Without ID Is Illegal"

Taniwha — Tue, 03 Feb 2026 02:19:42 +0000

It's security theatre, someone has to pay the performers

New comment by Taniwha in "The Cathedral, the Megachurch, and the Bazaar"

Taniwha — Mon, 19 Jan 2026 03:20:25 +0000

Yes but Cathedral and the Bazaar was telling us that the world had changed, gcc was free, linux was a thing etc, mainframes (where compilers cost $10k and you (mostly) couldn't bring your own OS) were being replaced by workstations etc.

Commercial access to Unix source was still many thousands of dollars, the whole SCO debacle was an attempt to stop free OSs from being a thing

Many of us who had grown up from the mainframe era wanted to write compilers, work on OS's etc etc it was a hard thing to do (esp. outside the US) before the late 80s, cheap commodity hardware let a thousand flowers bloom

New comment by Taniwha in "The Cathedral, the Megachurch, and the Bazaar"

Taniwha — Sun, 18 Jan 2026 22:29:44 +0000

Yeah, it's worth remembering that at the time a compiler cost $10k+, an OS $1000s/year - you couldn't work on OS or compiler work unless you worked for a big hardware company - a whole lot of interesting work was locked away from most programmers

New comment by Taniwha in "Dealing with abandonware (2024)"

Taniwha — Tue, 06 Jan 2026 06:00:41 +0000

You can go to this effort to get it to make the right magic number .... or just find the place where it gets tested and replace the conditional branch with a unconditional branch (or a no-op)

Having said that I once wrote 68k code that was an executable copyright message, and other code that if it discovered it wasn't running on an authorised machine logged to a known port, sent an email, unlinked the binary, queued "sudo reboot", killed the parent process and then exited (all the authorised machines were mine, running a bespoke kernel)

New comment by Taniwha in "Pure Silicon Demo Coding: No CPU, No Memory, Just 4k Gates"

Taniwha — Sun, 21 Dec 2025 00:35:57 +0000

TT allows you to pay more and build multi-block designs