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• Post #4487474

  Once again I have become @foone@digipres.club

• Post #4453536

  This pixel-art cow is the header of a valid DOS executable, encoded as UTF-8 Braille characters. See the whole thing here: https://github.com/dbalsom/executable_unicode/blob/main/hello_world/BRAILLE.COM Try it in DosBox! #retrocomputing #asm #x86

• Post #4440726

  UTF-16 has issues with endianness. You have to specify if your UTF-16 encoded document is big or little endian, which you do with a Byte Order Mark or BOM, of 2-3 bytes. FE FF - Big Endian FF FE - Little Endian EF BB BF - UTF-8 UTF-8 has no endian concerns so the UTF-8 BOM has little purpose I can see other than to annoy you when you're trying to read CSVs with Python

• Post #4425578

  Time for a new thread. I've made a short blog post outlining the basic techniques of executable emoji, which I have dubbed emojissembly. https://martypc.blogspot.com/2026/08/executable-emoji.html I started working on a general COM2EMOJI utility that I might post at some point, but let's face it the chances of me being distracted by some shiny thing in the next 48 hours is quite high.

• Post #4400568

  i wonder if you could make a useful DOS executable with just emoji

• Post #4400207

  i usually like staging but DosBox-X's 8088 emulation is more accurate. why am i not using my own emulator? because it's a low level emulator and i have to reboot the entire machine when i hang the CPU. which i am doing. a lot.

• Post #4383112

  I love it when you can sort of finally congeal scattered projects together into something useful. This is a serverless, single-page x86 disassembler, that runs my marty_dasm disassembly library as wasm in your browser. It may be the only disassembler with specific, CPU-faithful architecture modes. You want to select 8088 and disassemble 0F as POP CS? Go for it. #retrocomputing #assembly #emulation

• Post #4365246

  Nand2mario beat me to this with his really cool microcode browser https://nand2mario.github.io/8086_microcode.html but this allows me to put my own spin on it.

• Post #4280423

  I drew the logo for the excellent Macintosh, emulator Snow. I'm not quite happy with it, though. I think it can be improved still. I think the screen needs to be 1px larger, to start. And I can improve the shading. I'm still not really happy with how it's just sitting in a random pile 'o snow. I was thinking maybe to turn it into ice, and have a reflection of the Mac in the ice, but maybe that would be too busy.

• Post #4278757

  This is the Tandon TM100-2A. It's not the original-original OEM floppy drive for the 5150, which was the TM100-1, a single-sided drive. It's a "full height" drive, meaning it took up an entire two bays, or one entire side of the 5150's 2x2 drive bays. #retrocomputing #ibmpc #floppydisk

• Post #4259654

  Sometimes when I buy stuff on eBay the seller throws in Other Stuff. Sometimes its cool, but I really wish they would ask first. I am now the proud owner of six c64 joysticks I didn't actually buy. It's hard to complain about free stuff except I have lots of stuff and now I have to find a home for six probably terrible c64 joysticks.

• Post #4253275

  Sector 96 has a bad address CRC, a bad data CRC, and is deleted to boot. That is why it is Very Red.

• Post #4225728

  Here's a FujiFilm 2" diskette, courtesy of @shayman@cosocial.ca . Thank you so much for sending it along! For a floppy disk aficionado this is a rare treat. The only compatible drive for it was sold with the Zenith MinisPort laptop. The format never caught on beyond that one model. There are some more photos here: https://www.computinghistory.org.uk/det/57098/Fuji-Film-LT-1-2-inch-Floppy-Disk/ #floppydisk #retrocomputing #vintagecomputing https://www.computinghistory.org.uk/det/80...

• Post #4183771

  Starting to see the light at the end of the tunnel on my floppy drive controller refactor. Of course after i'm done I will have like 100 different floppies to test to make sure I didn't break anything else. My goal is to have several basic copy protection schemes working, and be able to boot all versions of Minix, with both the Tandy 1000 and PCjr able to read, write, and format floppies.

• Post #4177083

  I have this floppy cable I want to use, but there's just one problem. Some asshole has put a twist in it.

• Post #4176465

  so, a thought. a potential hack. maybe one for @foone@digipres.club The IBM floppy controller uses a NEC 765. The NEC 765 can support four drives, but IBM didn't really use that functionality directly. The NEC has two "Unit Select" pins intended to select a drive. For whatever reason, IBM didn't connect them, and instead added an external register called the Digital Output Register (DOR), with which you actually select the floppy drive you want to use.

• Post #4120686

  Floppy drive sounds in MartyPC 0.4.2! Here no disk is actually in the drive - what you're hearing is the stepper motor seeking during POST in GLaBIOS. Why does the BIOS seek the drive on startup? It's trying to determine what types of floppy drive are present. If it can successfully seek past track 40, it knows it is not a standard 360K DD disk drive. #retrocomputing #emulation

• Post #4118761

  I need a cute graphic for allowing you to shove a 3.5" disk in a 5.25" drive or vice versa. I allow this for convenience sake, but I want you to cringe while you think about it.

• Post #4117950

  Pixel artists are relatively easy to find if you needed artwork done for a game, but I find sound designers are a lot less frequently encountered. if i wanted to commission a startup sound effect for MartyPC, maybe a second long, any idea how much that would cost, as a ballpark?

• Post #4106763

  here i am labelling floppy drive seek sounds. i used a batch script and the greaseweazle utility to record a TEAC FD-55 seeking back and forth, starting with track 1 and 40, then back to track 2, then back to track 39. In this manner i could capture all seeks from 39 to 1 tracks. unfortunately, seeking backwards sounds different than seeking forwards, but i'm not really going to sweat that right now since i will eventualy need to redo all the sounds with an original Tandon drive, anyway....

• Post #4097025

  the label is crying out to have "killer jamz" written on it i think

• Post #4079740

  my cat has no idea how much he negatively effects my productivity

• Post #4075582

  I think we should train Large Unintelligible Screaming Models

• Post #4069985

  There, in the middle of the open floorplan, sat Dave, typing code directly into an editor like a madman. "He's not even prompting", Susan whispered with an astonished breath, standing huddled with a few coworkers that were all observing Dave from a safe distance. "How does he even know what to write," Susan asked, almost pleading for an answer, but all that came was a chorus of confused muttering. Dave's manager, Bill, put down his coffee cup with an aggressive cla...

• Post #4049885

  when you're nonbinary you can't help but notice how many places just insist on calling you "mister" i always feel like a dick correcting them because they look at me weird. like they'd probably be fine switching to "miss" but "none of the above" has never occurred to them

• Post #4022422

  (CUPERTINO, CA) OpenGenomics Inc. today announced that their latest generation of MurderBeast escaped containment during a recent evaluation. "While evaluating the most recently spawned MurderBeast's capabilities, said MurderBeast was able to temporarily disable the containment field and ignore the input of its control collar," OpenGenomics spokesman Alan Packard said. "Unfortunately, as a result, the MurderBeast was able to leave the facility, travel to a nearby Arby's,...

• Post #4002850

  Look at these beautiful color floppy disks. #retrocomputing #floppydisk

• Post #3998734

  Tracked down a citation for my article on the CGA composite video. There are two main versions of the CGA's composite output circuitry, splitting CGA cards into "old style" and "new style" designs. The new-style designs feed color inputs into components of the luma signal. This better helps differentiate colors on a black and white composite monitor.

• Post #3996293

  Something I've been trying to track down and utterly failing at, maybe if I describe it some people will recall something. I had a coloring book that was a bunch of futuristic, sci-fi tanks. I thought it was very cool because they had detailed treads and things and tanks are cool. I am not sure what happened to it - I remember we bought it at the airport but I must have misplaced it somewhere because that's my only memory of it. Timeframe would have been mid 80's.

• Post #3966520

  The first idea that immediately came to mind was interpolation. We can calculate the precise mathy-math for a full cached time step one millisecond ahead, then in our microsecond steps we simply do linear interpolation.