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Adrian Chadd's Ramblings

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The great 2024/2025/2026 tech firings, and what happens to all that clue

So yeah, I was caught up in the Meta/Facebook layoffs in March 2026. There are a lot of parallels to the 2001 dot com bust, and I'd like to just briefly touch on one of them now. There's been a lot of layoffs over the last year or three in tech. I think the tech market has seen what, more than 100,000 in the last year alone? And most of those aren't due to performance. There are a lot of very…

Being accused of taking down a Data Centre, or "what happens when adrian is the only one who isn't oversubscribed on power?"

This happened circa what, 2008? 2007? I forget now. Anyway, it was a while ago now - and it wasn't my fault - but at the time it was pretty "wtf oh shit I'm in so much trouble" scary levels of scary. So here we go. Around that time I was running a little consulting / hosting company. I went into the data centre which hosted my equipment to install a second hand Dell I had acquired and tested. I…

Installing a 32k DS1386 into an SGI Indy that expects an 8k DS1386

The TL;DR is - you can't just plug a 32k DS1386 into an SGI Indy and have it work, as a bunch of stuff is wrong. The longer version! Here's a picture from the datasheet: Now, at the outset it looks like A13 and A14 on the 32k module need to at least be grounded - if they're floated or high then the RAM will be selected when you don't want it to be, and you'll just fail to see the RTC. However, if…

Blinking the SGI Indy Power Light

I figured out what broke in netbsd to make the R5000SC I have here poweroff during startup. In any case, the hack for blinking the front panel LED, inspired from their BLINKY driver, shouldn't be lost when i clean up my tree. So, I give you all: +void +blink_led(void) +{ + uint32_t reg; + uint32_t i; + + reg = *(volatile uint32_t *)MIPS_PHYS_TO_KSEG1(0x1fbd9870) & 0xff; + reg = reg ^ 0x10; /*…

Reverse Engineering the SGI Indy Monitor Detection, or "thank god someone added SGI indy / indigo 2 support to MAME"

I have a bit of a soft spot in my heart for the SGI Indy and (purple, not teal, heh) Indigo 2. So imagine my surprise when NetBSD "almost" booted just fine on the Indy I have acquired. R4600PC-100, XL8 graphics .. and wonky console colours in netbsd / wonky xorg. The first deep dive is "why are the monitor colours so unpredictable?" and that got me into a fun deep dive into how the SGI Indy…

A tale of an SGI Indy, a Sony power supply, and how to keep the fan spinning

Let's not dwell on why I bought an SGI Indy. Anyway. One of the common things that I've seen is failure due to power supplies or heat death. The irony is: The Nidec power supply has dirty power, fails hilariously, but the fan is at least always spinning, and The Sony power supply has clean power, less hilarious failures, but the fan only comes on when the unit is hot. Sometimes. The fan in the…

Installing FreeBSD-15 directly on an SSD, or "wait this 2007 era AMD K8 1RU server doesn't boot from USB flash?"

I .. ok let's not talk about why I'm putting freebsd-15 on an old K8 era box. (it's for network hijinx testing with old realtek PCI cards, don't ask.) Anyway it's an award BIOS from 2007 that has the following USB options: USB FDD USB ZIP USB CD-ROM .. and doesn't like whatever FreeBSD is doing to the USB flash drives these days. Anyway, that meant I needed to figure out how to bootstrap FreeBSD…

Getting a Gotek working on a PCW9512

I acquired a PCW9512 motherboard a year or so ago and I really wanted to get it up and going so I can build a little case for it and turn it into a proper CP/M plus hack machine. The challenge? Getting a Gotek working on the PCW9512. There are some .. issues. Specifically - the flash floppy support needs some extra options and board modifications to support the drive detection that the PCW boot…

Fixing a dead Amstrad PCW9512+, Part 2

In my previous post I yanked enough of the PCW9512+ apart and debugged why the power supply just plainly wasn't working. Now it's time to see if the rest of the board was working. The first thing to do is test the power supply without having the 9512+ logic board (and the CRT side) powered up. The switch mode supply may not be happy with a load, so an initial failure isn't necessarily fatal. So it…

fixing a dead Amstrad PCW9512+

I'm on a bit of a "i wish I had a PCW as a kid" kick. So yeah, I have a working out of the box PCW8256 that has been upgraded to a PCW8512 (but with only one floppy drive for now. Stay tuned.) I got lucky; that one was in the US and didn't need any modification to work here. (And, amusingly, although it's setup for US power - and shipped with locAscript instead of locOscript, it's still configured…

On "repairing this commodore 1551 drive" and "don't plug in the head cable backwards"

I bought a "dead" 1551 drive a few months ago. It's a european model, only 220v, and they said "it smoked when it was on". Well, i figured it was dead but I figured maybe not dead dead. So, step one was removing the .. huge ass transformer. I stripped off the regulators and hooked it up to a pair of bench supplies to feed 5v and 12v with a current limit. (And yes, by this stage I had done a bunch…

Reinstalling AmigaOS 3.1.4 on my Amiga 2000 or "oh crap it didn't boot"

This post is about AmigaOS 3.1.4 on my Amiga 2000. AmigaOS 3.1 from Amiga works fine. However, there are a few interestingly subtle differences between 3.1 and 3.1.4 that are worth knowing about, and they stem from both OS and ROM changes that you need to be aware of. Let's start with why I reinstalled it. I did it a few months ago and didn't notice that I had only allocated a 10 megabyte OS…

resistance is not futile, or "why does my amiga 1000 keyboard not work?"

I gave my amiga 1000 keyboard cable to a friend so she could complete her Amiga 1000 setup. I then ordered some replacement RJ12 cables (4 wires!) to get mine working. But they didn't. Let's talk about why. Firstly - yes, the cable is a RJ12 4P4C rollover cable. Ie, if you hold both connectors up next to each other and aligned the same way, the left hand pins are numbered "1-2-3-4" and the right…

I got lucky with an Acorn Electron

Ah, the Acorn Electron . Wait, no. I never had one as a kid, I had access to a couple of BBC micros in my primary school for playing a pirate / math educational game that I have since not found online, and I've never really wanted one. Until a close friend's birthday - at which point I got them one. And then we fell down a rabbit hole together. So, I bought a dead Electron motherboard. Here you…

Who's the /BOSS on the Amiga 2000 ?

I slipped and bought a TF536 to put into my Amiga 2000. TL;DR is it's now running, but it took a bit of fiddling to get there. When I was last getting it going I noticed it didn't like any Zorro-II RAM in there, so I simply disabled it (it wouldn't do much) and left it alone. The storage card I'm using (a GVP SCSI job) doesn't do DMA to Zorro-II RAM - it does DMA to/from a 64k IO/RAM window which…

damnit i slipped and (mostly) built an amiga 500

EDIT - the original article has an image of the PCB with the floppy power connector mounted the WRONG WAY. This is the INCORRECT WAY. Do NOT do it this way! TL;DR - I'm half way through building an Amiga 500+ replica. The goal: New PCB New clear case Actual floppy drive! TF534 Accelerator, yes I am interested in FPU stuff for reasons and yes I'm sad about the 4MB of RAM but I'll make do -…

Installing a kickstart ROM adapter in my Amiga 1000, or "Nothing works, and nothing makes sense"

The Amiga 1000 is a slick looking machine. It however loads its ROM from floppy disk. The Wikipedia Article on the Amiga 1000 explains why. I wanted to put a Kickstart 1.3 ROM in my Amiga 1000. There are adapters out there you can build and install. I chose one, followed the instructions, and it didn't work. After a whole lot of digging I finally got it working and now I'm documenting what…

Fixing a third commodore plus/4, or "god damnit adrian stop it"

Here's a fun and easy one to fix. One commodore plus/4. Here's what it displayed. Looks like the TED chip is outputting something, but it isn't setup right. So I pop it open. There's the right clock on pin 1 of the CPU - switching between 1 and 2MHz as it does. Ok, so let's check the ICs. Hm, there's something wrong with the CPU pins. And this socket ... is kinda busted looking. One whole side of…

Getting new simgen backdrops on my amiga 500

This'll be nice and short. I wanted to add some new backgrounds to simgen, which is a hack on Amiga Workbench 1.3 setups which allows for a 1 or 2 bpp (2 or 4 colour) background image. Part of it is figuring out how to convert to a suitably formatted IFF (interchange file format) for an Amiga. I didn't want to install photoshop or do photo conversion on the Amiga. Yeah I'm lazy. So the TL;DR is:…

It took me WAY too long to get this gotek to work...

The short version - when you buy an actual OG Gotek with the OG Gotek firmware, it doesn't work in any convenient way that is documented on any of the retro computing sites, because you DEFINITELY need to flash it with different firmware. Ok, so the less short version! I picked up a busted Amiga 500 for free to help repair an Amstrad CPC464 for someone. It had a busted ROM socket, busted RAM and…

Amiga 1200 - Kickstart 3.1.4 upgrade, but not upgrading to AmigaOS 3.1

So I splurged a couple bucks on the updated AmigaOS 3.1.4 from Hyperion. It came with both the ROMs and AmigaOS. Now, I have 3.1 installed already, and I wanted to just drop in the ROMs. It almost worked. It looks like they moved some libraries from the ROM out to disk/RAM in order to make space. So I figured they were on one of the installation disks, and.... Easy peasy. I copied icons.library…

At least cross compiling for the Amiga 500 is easier than the 16 bit DOS mode PC stuff

I wanted to hack on Amigaterm ( https://aminet.net/package/comm/term/amigaterm ) a bit, but I found out that someone already had done that ( https://aminet.net/package/comm/term/amigaterm_enh ). They fixed some bugs and added speeds above 9600 baud - 19200 works fine on the Amiga 500, and 38400 works fine on the Amiga 1200. But I wanted to add a couple more things - play with what Amiga calls…

Getting stuff onto the Amiga 500, or "holy crap please include bootstrapping serial file transfer utilities in your OS"

Yes, I know I'm ranting about 1980s OSes, but to be quite frank, modern OSes on a variety of hardware still have a similar problem. Wait, what do I mean you ask? Surely you will always have ethernet/wifi/USB available? I almost started writing a bit on that here given I end up working behind the scenes on modern hardware and a LOT has to be working before you can talk over the network or, heck,…

Hacking up an Amiga 500 for 1MB chip RAM and 512k slow RAM

In a previous post I dumped a bunch of information I had learnt about what had happened in open source Amiga hackery. I've now gone and committed the initial hacks needed to prove that it works and document how I did it. My goals here were: Build one of the memory expansion Gary adapters that are out there - I chose the PeteAU design that I've checked in here ; Figure out how to modify a rev6…

Figuring out how Amiga 500 RAM expansion projects work

(Wow, what a shift in topics here..) Yeah I picked up an Amiga 500. Specifically, a rev6 amiga 500. It has 4 extra spots on the mainboard for another 512k of chip ram that isn't populated. Crap I'm going to have to explain chip RAM. Ok, so the Amiga is a pretty nifty architecture, especially if you realise it was designed in the early 80s. I won't go into it all because that's not the point of the…