Chris Covell

@chriscovell.bsky.social

I'll be posting retro gaming, retrocomputing, and retro dev stuff. Canadian living in Japan https://www.chrismcovell.com/

Did anybody else growing up in the '80s have this book, Amazing Days? (actually 366 days...) Each day had some historical note or fun project to do, plus a diary writing space. I finally found this one after a bit of searching...

The Kids' Diary of 365 Amazing Days by Randy Harelsontwo pages showing the Amazing Days book inside. Making an origami boat, "halfway day", and Canada (Dominion) Daytwo pages showing the Amazing Days book inside. Sci-Fi celebration, wax paper drinking straws invented, and Braille

HardOff shop in Kokubunji had this KOYO KTR 1661 multiband radio (from 1965!) for an amazingly low 1000 yen. It's in rough shape, but still received FM and shortwave when I tested it -- a no-brainer to snap up! It picks up airplane communications as well, but rather low sensitivity. Still, a beauty.

A KOYO KTR 1661 multiband radio from 1965

Random game Saturday: I sent myself some old games, magazines, and that sticker album I had kept in storage for over 20 years. Among them was this great 4-in-1 bootleg MegaDrive cartridge. One great game, 2 decent ones, and then Street Smart. :D

A 4-in-1 MD cartridge with Wani Wani World, Juju Densetsu (Toki), Alien Storm, and Street Smart

Some more of my old sticker album pages from the mid-80s. E.T. & Labyrinth really date these ones. The Transformers stickers probably came a bit later. The Beachcomber and Warpath ones have an outline that glows in the dark. 🕶️🔦

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I put my Greaseweazle and Y-E Data floppy drive back into its nice case & covered holes/panels with layers of folded-over plastic (works OK all things considered). The GW has vias to wire external LEDs, but no matter which LED I tried, they were all quite dim. I stuck with the original unit's LEDs

A repurposed MS-21D-FD drive for reading via GreaseweazleActivity LEDs. Works great!Rear of the MS-21D-FD. Don't look too closely!

This is an odd one... your reg. 3.5" floppy drive from TEAC or whatever runs at 300rpm, but the YE Data drive from the MS-21D computer rotates at 360rpm. Greaseweazle can read and write disk images & flux just great from it, but HxC seems to hate it. (No seeming way to adjust its speed too.)

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The MS-21D-FD contains a Y-E Data YD-686C floppy drive which has 5V on 3 pins on the ribbon connector; definitely not good! I found a jumper (highlighted pink) that disconnects those from 5V power, soldered in my own power pins. Also had to move a jumper (green) from '0' to '1' for it to respond.

Location of jumper on Y-E Data YD-686C floppy drive to isolate 5V from the pins on the ribbon connectorY-E Data YD-686C floppy drive underside showing 3 offending 5V pins (yellow) and a jumper I had to bridge for the Greaseweazle to communicate with itY-E Data YD-686C floppy drive label. 1991 year

I received a Greaseweazle this week to work on backing up & analyzing floppy disks. Works great! I also happened to find a Japanese "Microsystems MS-21D-FD" proprietary floppy drive for an old obscure computer. Beautiful red & black look but it needed some modifications to run as a regular floppy...

The MS-21D-FD floppy disk driveMS-21D-FD disk drive runs on 100V AC. It looked like it communicated via serial or parallel but those are just 2 breakout ports for the host computer. Interesting...Inside the MS-21D-FD. Broken AC power supply; and power is delivered to the floppy via the 34-pin ribbon connector.

Not a lot of info about this GB floppy copier. Made by CCL in 1998-99ish. As I had said, when writing games to floppy, it just clobbers over existing formats with its own 16-sector/track format (standard 1.44 FDs use 18 sectors/track). Old SNES copiers can read the disk, but modern Win PCs HATE it!

Image taken from online console database. Thanks!  Note the different button colours from the real unit's R,Y,G,B.ROMs are saved as "GBC_GAME" with a .1 or .2 extension with files that exceed 1024K. Save RAM also gets saved with the .sav extension

A white unicorn has appeared! The "GB Smart Development Kit" was a standalone GameBoy cartridge copier that saved dumped games to FDD, and could load them onto a rumble SmartCard. Really primitive FAT functions that formats as it writes the ROM to 16-sector-per-track High Density FDD only.

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Here's something wild: I thought I found a bug in my FAT12 LFN (long filename) code, but it turns out that the checksums for the files "GREEN.SMC" and "SUPERF~1.BMP" both add up to 0x48, causing a bit of an identity crisis. How did OSes like Windows handle these cases?

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My old binder also had tons of design patents for the NES/SNES/Gameboy systems, the Game Genie, etc. These were easily searchable from the US Patent Office's webpage in the late '90s. Are they still easily searchable?

Patents! Here showing how the Super Famicom is put together, and the Gameboy.

In my storage, I found the large binder I kept for NES & 6502 programming, from the late 1990s. I printed out tons of pages of documents and this was a valuable reference. I decided to donate this binder to my best friend's game-loving programmer son.

The front cover of the binder showing an EPS Nintendo drawing I made, plus the NES' paletteThe first page of the binder showing tabs or post-it notes separating documents and sectionsAn early printout of the NES architecture page by Marat FayzullinA printout of the early Disk System format doc by Goroh

I've come back from a family vacation to my hometown, Vancouver, Canada. I had a little time to sort through some old bins in storage. Found the old boxed games! (Well, some of them.) The Dr.PCJr. box didn't contain the system, since I had taken it with me to Japan...

A storage bin containing NES, Turbografx, and Master System, etc. game boxes. Also the box for the DrPCJr Famiclone/computer.

Been busy but have found some time to keep modifying & enhancing the Super UFO 8 floppy SFC copier. I made a help screen for all the added controls, plus I've converted the built-in Action Replay cheat codes to an .asm include file, in order to trim/add more codes.

Help menu describing controls for my modded UFO BIOSA snippet of ASM code/bytes describing AR/X-T cheat codes

The UFO 7.2 J なにわ "Naniwa" version is in Japanese only. And the name なにわ refers to the area in Osaka; as such, messages in this copier are written in the Kansai dialect: Game save? おまへん(Ain't here!); How's the checksum? あかん(No way!); Disk in drive? いれてんか?ディスクガナイデ!(D'jya put one in? Ain't seein' it!)

UFO Bios 7.2 Naniwa on left showing some Kansai dialect; English UFO 7.3 BIOS on the right

A Super UFO 7 SFC copier just fell into my lap this week, and it's a kinda rare Japanese 7.2 なにわ "Naniwa" version. This one came with a protective hologram over one screwhole, so: pics! The BIOS is on a 32KB EPROM, whereas the 7.3 version adds built-in X-T cheat codes and is on a 64KB EPROM. Neat!

The Super UFO Pro 7 SFC floppy copierCool UFO "High Technology Product" hologram stickerThe instruction manual cover for the *7.3* Naniwa version, distributed by GameTech around 1994? ~ 1996?

The "Pro Fighter X" series of SNES copiers has kinda stupid disk handling code: it doesn't filter out FAT entries on floppy disk that should never be displayed, like the Volume name ("CHRIS"), directories, and long filename chunks. This causes errors during display & loading. So I RE'd and fixed it.

"Pro Fighter X" SNES copierIt's displaying the volume name first, "CHRIS" then overlaying invalid entries into the file list. Also tries to load invisible files...My disk fix code. Done through a bit of searching and trial-and-error, since these BIOSes don't run on emulators, and no SNES emu emulates floppies anyway...Pro Fighter X file display fixed up!  Also with a new tilde glyph added into the font, as well as a new custom SFC background

I did what the UFO guys never bothered to do: about a week ago, I read up on how Long File Names (LFN) work on FAT12 floppy storage, and programmed in a display routine for LFNs on my Super UFO8 FDD copier. Much more useful now!

The Super UFO 8 copier displaying long file names

The UFO 8 (FDD) Super Famicom copier has a realtime savestate feature which also lets you examine PPU backgrounds and sprites from the savestate. You also can view the Mode7 BG, but only *view*. I've added my own routines in the UFO BIOS to let you scroll, scale, and rotate around the Mode7 BG.

4 snapshots of the Japan map screen in SFC Ganbare Goemon rotating in Mode7, using my hacked program in the Super UFO

The BIOSes for the "UFO Super Drive Pro-6 Hyper Version" come in a 27256 EPROM, but only have the upper 16KB used. In addition, the copier uses an 8K bankswitching method, so these will probably never run in an emulator. So, using the 1bpp CHR graphics in the BIOS, I've made digital reconstructions.

Digital mockup image of the UFO 6 Jp version BIOS screenDigital mockup image of the UFO 6 3.1 (English) version BIOS screen

I found a UFO Pro6 SFC copier for cheap recently. The UFO line of copiers is great, and this one is a... primitive step along the way. While the UFO 7 & 8 had built-in cheat codes for games, the 6 didn't, so it let you store AR and Goldfinger codes directly in the 512-byte copier header of each game

A UFO 6 pic with box taken off the Web. Thanks!My UFO 6 came with the Japanese "TOKIO" v3.0 BIOS, which I changed for the English 3.1 one. Both versions load disk games in normal or "hyper" mode w/ cheats on. The [*] star modes do the same as the top options, and I have no idea how they are different...Aha, so this is what the 512-byte SFC copier header is for!
Golden Finger (ROM patch) codes saved in the UFO header of games stored on disk.