@mcmartin@mastodon.gamedev.place

McMartin @mcmartin@mastodon.gamedev.place

· 1w ago

Replying to

This week on the blog: the followup: working through my (eventually) successful attempts to play good digital audio out of the ZX Spectrum's 1-bit beeper! Also some 10,000-ft looks at the prior art on the Spectrum and the Apple II to round it out. https://bumbershootsoft.wordpress.com/2026/09/26/digital-audio-on-the-zx-spectrums-1-bit-beeper/ #retrocomputing #zxspectrum #apple2

Bumbershoot Software

Digital Audio on the ZX Spectrum’s 1-Bit Beeper

It’s finally time for me to wrap up this ZX Spectrum series, with a look at how to get the simple 1-bit beeper on every Spectrum model to emit high-quality digital audio. The results are quit…

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McMartin @mcmartin@mastodon.gamedev.place

· 4d ago

This week on the blog: Quieter week as I take some time off of the Spectrum and the Z80. I read some books I'd picked up at prior Vintage Computer Fairs, and that inspired me to write a bit about the PDP-11 and medium-scale BASIC development back in the early days.

https://bumbershootsoft.wordpress.com/2026/10/03/book-reports-from-vcf-west/

#retrocomputing

bumbershootsoft.wordpress.com

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McMartin @mcmartin@mastodon.gamedev.place

· 3w ago

Made some progress on my Sinclair PWM experiments. No sample playback yet, but I can generate a proper sawtooth wave, which means I should be able to convince Fuse to behave enough to *do* sample playback.

#retrocomputing #zxspectrum

mastodon.gamedev.place

Gamedev Mastodon

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McMartin @mcmartin@mastodon.gamedev.place

· 1mo ago

This week on the blog: Posting some photos from this year's Vintage Computer Fair.

https://bumbershootsoft.wordpress.com/2026/08/22/vintage-computer-fair-west-2026/

#retrocomputing #vcf2026

bumbershootsoft.wordpress.com

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McMartin @mcmartin@mastodon.gamedev.place

· 5mo ago

Replying to

I'm still interested in finding good *modern* tutorials for the 8- and 16-bit CPUs. 6502 has several good ones (https://skilldrick.github.io/easy6502/ is the go-to), but I haven't found any nice modern preferably-interactive tutorials for the Z80, 6809, or m68k. Any of you know of any? #retrocomputing #z80 #motorola6809

skilldrick.github.io

Easy 6502 by skilldrick

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McMartin @mcmartin@mastodon.gamedev.place

· 6mo ago

Hey there retrocoding friends. Indirectly prodded by @pervognsen@mastodon.social I decided to dig out my old GBA stuff and then try to put together a quick "platform guide" for my blog: a round up of resources and resource hubs, along with just enough information to get bare-metal dev off the ground and clear away any toolchain nonsense.

Here's what I have so far, but I bet there are some GBA devs out there who can help me expand it. Any takers?

https://bumbershootsoft.wordpress.com/platform-guide-game-boy-advance/

#retrocomputing #gba #gbadev

Bumbershoot Software

Platform Guide: Game Boy Advance

Wikipedia article: Game Boy Advance Last updated: 28 Mar 2026 The Game Boy Advance is an anomaly for this collection: it was released in the 21st century and was contemporaneous with the GameCube, …

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McMartin @mcmartin@mastodon.gamedev.place

· 1mo ago

This week on the blog: Some stuff I didn't get to in the ZX Spectrum tour. I've been trying to get better sound out of its 1-bit speaker and the results have been... mixed. I've still got some homework left to do but I got some *very* nice chord progressions out at least.

https://bumbershootsoft.wordpress.com/2026/09/05/zx-spectrum-experimenting-with-1-bit-sound/

#retrocomputing #zxspectrum

Bumbershoot Software

ZX Spectrum: Experimenting With 1-Bit Sound

As part of the ZX Spectrum tour, I implemented some routines that would let you play simple tones out of the 1-bit beeper. These were in large part inspired by earlier work I did on the Apple II. W…

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McMartin @mcmartin@mastodon.gamedev.place

· 1mo ago

This week on the blog: Finishing my tour of the base ZX Spectrum hardware by looking at the memory mapper in the 128K version, with a nod to the +2 and +3 successors.

I'm not totally done with the platform, but now that I've looked closely at everything I saw in my initial tour, I'm shifting gears for a bit before I return.

https://bumbershootsoft.wordpress.com/2026/08/15/zx-spectrum-system-tour-memory-mapping/

#retrocomputing #zxspectrum

bumbershootsoft.wordpress.com

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McMartin @mcmartin@mastodon.gamedev.place

· 1mo ago

This week on the blog: I just finished accomplishing a fancy ZX Spectrum port of a project I'd done a half-dozen times already. I set about bringing the fancy parts back to earlier systems and then end up source-diving my favorite emulator instead.

https://bumbershootsoft.wordpress.com/2026/08/29/spectrum-shooting-gallery-taking-back-what-weve-learned/

#retrocomputing #colecovision

bumbershootsoft.wordpress.com

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McMartin @mcmartin@mastodon.gamedev.place

· 1mo ago

I've been focusing almost entirely on the ZX Spectrum for my hobby stuff since May. Now that I've gotten a few projects under my belt, I'm comparing what I've learned and remembered from a guide written by Jonathan Cauldwell, a prolific author for the platform past and present.

This week on the blog!

https://bumbershootsoft.wordpress.com/2026/08/08/zx-spectrum-comparing-notes-with-an-old-hand/

#retrocomputing #zxspectrum

bumbershootsoft.wordpress.com

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McMartin @mcmartin@mastodon.gamedev.place

· 5mo ago

Replying to

@eniko @thomholwerda I am told that they also have the best solutions to the bin-packing problem in the logistics industry and it's not remotely close. I'm staying out of the rest of this thread because I spent Friday night neck-deep in assembly language both human- and compiler-generated and The Rules Are F'in Different There

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McMartin @mcmartin@mastodon.gamedev.place

· 2mo ago

This week on the blog: I get enough out of the ZX Spectrum's various sound chips to match what BASIC offers. Still struggling a bit to replicate my digital-sound-effect techniques, but that just means there'll be a follow-up post at some point.

https://bumbershootsoft.wordpress.com/2026/08/01/zx-spectrum-system-tour-sound/

#retrocomputing #zxspectrum

bumbershootsoft.wordpress.com

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McMartin @mcmartin@mastodon.gamedev.place

· 2mo ago

This week on the blog: Adding shots to our shmup. Possibly also intentionally architecting things wrong to see if they're bad ideas. (Conclusion: Maybe? But it's pretty close to a even set of tradeoffs.)

https://bumbershootsoft.wordpress.com/2026/07/25/finishing-the-zx-spectrum-shooting-gallery/

#retrocomputing #zxspectrum #z80

bumbershootsoft.wordpress.com

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McMartin @mcmartin@mastodon.gamedev.place

· 5mo ago

Replying to

@icecreamjonsey@mastodon.gamedev.place @aachrisg@mastodon.gamedev.place Now, the heavy metal poisoning...

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McMartin @mcmartin@mastodon.gamedev.place

· 5mo ago

Replying to

@TomF@mastodon.gamedev.place I have long held this, and I have also long held that you should know one level "up" as well. An asm programmer must know how to build functions. A C programmer should be able to synthesize vtables, closures, and Rust-style matchable enums as required. And so on.

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McMartin @mcmartin@mastodon.gamedev.place

· 8mo ago

Boosted by @flargh@mastodon.social

This week on the blog: I go close some gaps in my understanding of the capabilities offered by the TI-99/4A's firmware. Now that I've picked up a working knowledge of most of the underlying hardware, on the system itself and its successors, I can see a bit more clearly. https://bumbershootsoft.wordpress.com/2026/01/17/ti-99-4a-leaning-more-heavily-on-the-firmware/ #retrocomputing #ti99_4a

Bumbershoot Software

TI-99/4A: Leaning More Heavily on the Firmware

I kicked off last year with a look at the TI-99/4A home computer. I’d started out playing with BASIC and then moved on to translating some of those BASIC programs into machine language and it…

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McMartin @mcmartin@mastodon.gamedev.place

· 5mo ago

Replying to

@TomF@mastodon.gamedev.place @JamesWidman@mastodon.social Preparing something like this is also the most absolutely brutal code review you can ever submit yourself to

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McMartin @mcmartin@mastodon.gamedev.place

· 5mo ago

Replying to

@gkrnours@mastodon.gamedev.place Modern gcc is also extremely good at compiling for the m68k; the recent Genesis release "Earthion" explicitly credits a gcc-based SDK in its toolkit credits

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McMartin @mcmartin@mastodon.gamedev.place

· 5mo ago

Replying to

@csepp@merveilles.town But there's this *wistfulness* I see around asm and embedded or retro programming like it's an impossible feat accessible only to the mightiest of wizards and it's just not. It is, at worst, really inconvenient to get all the pieces together. The hard part of retro asm isn't the nuts and bolts, it's being able to organize anything of meaningful size out of such small parts!

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McMartin @mcmartin@mastodon.gamedev.place

· 5mo ago

Replying to

@csepp@merveilles.town I'm a big fan - I just wrapped up a little PICO-8 project that I still need to properly write up and put a bow on - but for it's being a different thing. PICO-8 is about firing up something like an 80s home computer and getting it to do cool stuff within the strictures it offers, but it's working at a level where you're thinking about the cool things. This is, of course, very cool.

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McMartin @mcmartin@mastodon.gamedev.place

· 5mo ago

Replying to

@colinstu@birdbutt.com @gabrielesvelto@mas.to @emilvolk@tiggi.es There was an excellent thread by @TomF@mastodon.gamedev.place on this topic recently: https://mastodon.gamedev.place/@TomF/116461315315659325 What you really need to know is your *adjacent* levels. It's much more important for a C# dev, say, to know how their garbage collector works than what, exactly, their JIT is producing! It also kinda means writing *modern* asm isn't productive unless you need to directly instruct the cache or branch predictors, and that's another reason to stay retro for asm these days...

mastodon.gamedev.place

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McMartin @mcmartin@mastodon.gamedev.place

· 5mo ago

Replying to

@TomF@mastodon.gamedev.place I'd say even Quake doesn't quite have it at the start. Default controls used mouse buttons for motion! WASD had to be invented and IIRC it emerged from Quake's competitive scene. I played Descent back then and thought mouselook was obviously busted since it gave infinite turning speed so clearly this would just be a passing fad, etc.

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McMartin @mcmartin@mastodon.gamedev.place

· 5mo ago

Replying to

@jmac@masto.nyc This was more or less my reaction to https://sphere.computer/ but I did get to see one in the "flesh" at a Vintage Computer Fair a year or so back

sphere.computer

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McMartin @mcmartin@mastodon.gamedev.place

· 5mo ago

This week on the blog: I take a quick tour of the weirdest old computer that still ended up (very indirectly) influencing my childhood computing: the Exidy Sorcerer. Never had one, never saw one, but one of the big books o' programs I had as a kid was published as Apple II but started over on the Exidy.

https://bumbershootsoft.wordpress.com/2026/04/25/staying-a-spell-with-the-exidy-sorcerer/

#retrocomputing #exidy

Bumbershoot Software

Staying a Spell with the Exidy Sorcerer

The idea of what it means to be a personal computer has evolved over the years. The usual story is that Back In The Day you turned the computer on and were immediately in BASIC, while nowadays you …

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McMartin @mcmartin@mastodon.gamedev.place

· 5mo ago

Replying to

@ckent @eniko In this case the part that I feel I still need to properly organize my thoughts is the discussion earlier celebrating artistry in code. When actually trying to have software do the things we want software to do in society, artistry at the asm level is an *extremely* mixed bag - even when you bring the same core values in, the environment and context drastically alter the "derived" values that eventually read like moral maxims or even craft rules-of-thumb

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McMartin @mcmartin@mastodon.gamedev.place

· 3w ago

This week on the blog: Not enough progress on the sound stuff to write up, but I *did* finally sit down and make a proper cheat-sheet for cycle-exact delays on the systems I mess with.

https://bumbershootsoft.wordpress.com/2026/09/12/designing-cycle-exact-delays-on-several-8-bit-cpus/

#retrocomputing

bumbershootsoft.wordpress.com

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McMartin @mcmartin@mastodon.gamedev.place

· 5mo ago

Replying to

@gkrnours@mastodon.gamedev.place It's got a page in the guidebook, though! I'd stick to C if I messed with it though; I'm not sure I'd wish THUMB1 on anyone

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McMartin @mcmartin@mastodon.gamedev.place

· 5mo ago

Replying to

@lhauser@mefi.social It is an extremely good time to be getting into the Apple II. I've felt that the A2 community has focused heavily on preserving the usefulness of old hardware, compared to say C64 or Sinclair, but there's been a recent flowering of open-sourcing and rewritten tooling that make it much more pleasant to work with. The change in tone between my early Apple II crossdev articles and my more recent ones is *very stark*.

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McMartin @mcmartin@mastodon.gamedev.place

· 5mo ago

Replying to

@cdegroot@mstdn.ca I've got quite a few listed in the subpages, though (before this thread) I really didn't have what I felt were good tutorials for the modern reader. The book I learned Z80 from was more than 50% dedicated to loading the hex codes from your hand-assembled binary into RAM to be able to run them at all! I've also realized I want *labs.* That 6502 tutorial has an in-browser assembler and machine code monitor to play with as you learn. I want a whole zoo of those now.

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McMartin @mcmartin@mastodon.gamedev.place

· 5mo ago

Replying to

@cdegroot@mstdn.ca I started sketching up a list of "here's the books I learned from for these chips and here's the ones I recommend novices learn from" and I think I might need to rethink this because the only place where they're the same books is going to be the TMS9900 I'm pretty sure I learned 8086 from the gutter

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