Gooday Gaming Guests - SEGA Dreamcast and GameCube Code Process

Episode Date: January 19, 2025

Both the Use a constant CAV.

Alright, so today we're going to work on Sega Dreamcast. They call it the GD-ROM, is that what it is? I can't hold on. It's called, yeah, the GD-ROM, Gigabyte Disk ROM. It's not a CD-ROM, it's a Gigabyte Disk ROM, which includes a combination of hardware and software. So we're going to look at the kind of code format process of it the GD ROMs proprietary disk was stored up to 1.2 gigabytes of data 1.2 gigabytes of data which is more than the 700 megabytes on a CD so the gigabyte and I guess that

would make sense gigabyte disk ROM so So it is a GD ROM. I Always call it CD ROM, but it's a GD ROM Session one these discs contain two sessions on them. The first session contains standard CD ROM format and the second stage session Contains the actual game data in a high density track Which is not actually accessible by regular CD drives

so let's learn something new right there so it runs out of two different things when the DreamKey cast starts the BIOS checks for the GD-ROM it verifies the header boot and then it processes it. Security ring. GD-ROMs include a security ring, a physical feature on the disc not present on standard CDs. So there's a ring on there as well. Dreamcast Laser Assembly reads the ring to identify it's authentic. Once the GD-ROM is validated, the system loads the games

executable. The loader includes additional checks, homebrewed, and backup workarounds. Despite the protections, the copy was eventually bypassed due to vulnerabilities. The MIL-CD exploit,

some Dreamcast Council supported, a multimedia format called MILCD for playing audio and video. The hackers discovered that the MILCD format could be exploited to bypass security checks. The exploit enabled to burn Dreamcast games onto standard CD-ROMs. Though some limitations to the smaller size compared to the GD-ROM. I didn't realize that those were not the same kind of discs as the CD.

Modified bootloaders were created to make backup discs self-bootable by emulating the CD-ROM boot process. I think I have some discs that do that. I gotta go find that. There's. I think I have some just that do that. I've got to go find that. There's three discs that I have that I came across that have all the games on them.

At least a lot of them, anyway. Modern Solutions is the GDEMU, or Mode Multitask Disc Emulator, to bypass the GD-ROM. You use the SD cards, and then there's one you plug in the back so what's the game library of Dreamcast must have been a lot but it wasn't out that long though I believe it was a short run but Dreamcast I want to say maybe 60 games. Let's see.

So it says device, diverse, mix, arcade, third parties, though its lifespan was short, as I said. It's a game used to love by fans. So Sonic Adventure, Shenmue, Crazy Taxi, Jet Set Radio

Phantasy Star Online which I think you can still go online and do that, I think. I'm not positive. Sega Rally 2 Skies of Skies of Arcadia and Virtual Tennis.

Third party hits was Resident Evil Veronica, Soul Calibur, Dead 2, Power, Grando, Seaman, Bizarre, but intriguing virtual pet simulation featured a fish

with a human face created by Lennon Nemoid in the western release, Seaman. That's really strange. House of the Dead 2. Crazy Taxi. Nearly perfect port of the arcade classic. Regionals specific in Japan.

Saku Wars. Eldorado Gate Series. Nappa Tail. A charming 3D platform. Euro exclusive titles. headhunter third person action adventure that gained popularity in Europe headhunter home brood and Indian games rush rush rally racing and Exodia. So there's 620 games. Wow. Way off.

North America there was 250. Japan there was 460. Okay. That makes more sense. In Europe there's 200. So let's go look at some rare rare games. Let's see if we can have some rare rare games let's see we'll get some rare games so right now we're doing sega dreamcast and then we'll go on to of course the most popular ever sega gamecube

i mean uh i said sega no uh nintendo gamecube sega GameCube. Cannon Spike High. It included Mega Man and Capcom. It was at Capcom. Project Justice 2000. Sequel to Rival Schools, a 3D fighting game. Skies of Arcadia. Power Stone 2. These are all rare games Mars Matrix gigawings to res some

kind of shooter border down Ikanumi 2. Ikaruga. I'm not saying it right. Illbleed. Illbleed. A quirky survival horror game. With a bizarre sense of humor. And unique mechanics. It was a commercial failure. So let's check that one out.

Illbleed. I think that's survival horror I'm into. Of course everybody is. Let's see what that one is. If I get one that catches my attention I'll look let's find out so that's called Illbleed

this was a Sega Dreamcast but I do like I said I have a copy I have a copy of I think most of the games. I'll have to look up that one. It'll bleed. $136. Yeah, it looks kind of weird.

$205. $180. $170. $69. It'll bleed. $200. $150. $700.

So, it'll bleed. That's my... $200 $150 $700 so Illbleed that's my I always pick one game that's cool Illbleed so they're all in well even for Japan games they're really they're way over

$1400 in that little case thingy some of them are $100 cool so that's Illbleed well maybe at some point I'll look around for those I do have a Japan Some of them are $100. Cool. So that's Illbleed. Well, maybe at some point I'll look around for one of those. I do have a Japan Dreamcast.

Ducks 1.5 and Redux. Doc Matters. Shoot them up. Twinkles. Star Sprites. Cosmetics Smash. Alright, so... So we're going to go to...

Sega Dreamcast. Oh, I was going to go backwards again. Let's look at... So we did Sega CD. What's Sega? Powerbeast. Powerbeast. Cartridge. Code process.

I forgot that power base. The power base was compatible with Mega Drive. It uses a Z-Log Z80 processor. Graphics, memory, C mode selection, master system mode when a master system game is detected

the Genesis has a mode switch, the power base converter also that's the converter you put on top it uses a Z80 processor I think we've done this one Z80 compatible notes master system games

most were perfect with power base converter I'll masturbate cards and 3Ds light gun notes, Master System games, most were perfect with Power Brace Converter. MasterPay cards and 3Ds. Light Gun. Expandable capabilities, Mega System, Mega Cartridges, larger size. Mega System. So let's go on to it.

We'll go to GameCube then. Nintendo. Let's do a Nintendo GameCube disc code process. I have no idea what's going on with those. So they use the mini DVD format they that could hold up to 1.5 gigabytes on those little mini guys Proprietary design it was designed so that nobody could copy it Use a unique coding method to make a disc incompatible with commercial DVD players. You couldn't put it in a commercial You can put it in a we though right you can put it in a we check for valid mini DVD or thing you check so they use proprietary known as the game discs a special region near the hub of the disc that contains a cryptid uh it's called the burst cutting area

bca the bca is etched into each one of the discs so that's how they look for and the other ones were like ps1 was the wobble groove and and there was uh yeah i think wob Groove was on a couple different ones so game code execution the IBM PowerPC Gecko PC CPU generate the game code while the ATI GPU handles graphic rendering so preparatory disks the use of mini disks made it harder to copy the disc had those etchings on them description keys are stored in the game cubes firmware modding and workarounds. Despite the Nintendo's efforts. There's always a way around stuff. Soft mod exploiting. Exploits like the.

Fantasy Star Online Exploit. Allows users to run unsigned code. By leveraging network features. Mod code. Mod chips. What do they call that? Peek-a-boo. Peek-a-peek or something.

I have one of those, I just haven't finished it, programs like Swiss, enable users to run games, applications, optical drive emulators, the GC loader, replaces the drive,

region lock, Japan, PAL, or US, backwards compatible, it's not backwards backwards compatible to any earlier Nintendo systems. GameCube could only play GameCube.

However, if you had a Wii, you could play GameCube. What's a game library for GameCube? Let's see. What's that? What's the game library for the Cube? It had to be. library for the cube

had to be I want to say 1500 rich and diverse game library Smash Brothers Legend of Zelda, Wind Walker, I've never played that Metroid Prime Luigi's Mansion

Animal Crossing Mario Resident Evil 4 Metroid Prime Luigi's Mansion Animal Crossing Mario Resident Evil 4 Eternal Darkness Metal Gear Solid Twin Snakes Tales of Symphony Star Wars

Soul Calibur 2 Beautiful Joe multiplayers had multiplayers huh Smash Brothers oh we're aware Mario Kart double-dash had some uncontentional and experimental game Chi Chi robot Gucci survival the fittest odama I had that one odama a pinball reality game hybrid set in Japan pinball the popular ones were Simpsons beyond good and evil need for Speed Japanese only had Dasha and the Giant and Nintendo

Puzzle Collection So it was only 650 to 700 games North America we had 550 games Japan 450 In Europe there was 400

rare and collectible ones Fire Emblem Patience of Radiance Pokemon Box Ruby and Sapphire Go Go Hypergrind Disney let's see

rare rare game cube cube games so let's see rear cube it did give me some more all right so fire emblem was Pokemon Box, Ruby, and Sapphire We did that one Gotcha Force That's a Capcom game Interesting Survival of the Fittest

Cheap-I-Ruba Small robot cleaning the house Cult Classics Guys of Arcadia legends Resident Evil cold Veronica X pure evil 2-pack I mean basketball go go high Basketball Go Go High Grid Pokemon XD Glaze Glaze of Darkness Mario 7

with the microphone bundle Phantasy Star episodes 1 and 2 Tales of Symphony the collector's edition Tales of Symphony The Collector's Edition What speed speed

is the cube disk running at? Running at Let's see what the disk is running at. Running at. Let's see what the disk is running on for the GameCube. As opposed to another CD. So, the Nintendo GameCube and the MiniDV spin at a constant

speed thanks to the constant angular velocity. CAV method. Rotation speed, speed of 5.4 times. In CD-ROM terms, 1 times is 150 kilobytes per second. So 5.4 comes out to 3.24 megabytes per second the speed is optimized by

reading data from the smaller 8 inch disc while maintaining reliability and avoiding excessive noise the constant angular velocity cav unlike constant velocity a constant linear velocity CLV where the disc slows down as the laser moves towards the edge the game who uses CAV this spins at a constant rate regardless of the position of the laser oh yeah treasure I've noticed that the spindle never goes any faster. The simplified drive mechanics ensures a steady

data transfer rate. Comparison. So, GameCube and other consoles. PS2 standard ROM runs four times.

Approximately 5.28 megabytes per second. The Microsoft Xbox does five times and 6.75 megabytes per second while the gamecube was 5.4 times speed much slower than the xbox drive and smaller optimized game loading it says nintendo offset potential limitations of the disk speed so these are offset limitations games use custom compressed methods to minimize

file sizes stream data many games stream data efficiently to reduce load time, taking advantage of the steady data stream, disk access patterns, the smaller disk size reduced seek time for the laser. It didn't have to move up and back. So that's pretty interesting. What's the Dreamcast? Dreamcast disk speed. Because it's a different disk let's see what that is it's a GD-ROM right

we decided that the GD-ROM now is oh so it's at 12 times speed so GD-ROM because it was a gigabyte so it was bigger than a regular CD had the 12x speed. That's why they're so loud, those laser boards. 1x for a CD-ROM is 15, 150 kilobytes per second.

12x speed is 1.8 megabytes per second. For GD-ROMs, which is a tensor, the affected data transfer rate is 1.2 megabytes per second. For GD-ROMs which is denser, the affected data transfer rate is 1.2 megabytes a second. GD-ROMs doled up to 1.2 gigabytes. Use low density area, high density area, use two areas. Then I also used a constant angular velocity, CAV, just like the GameCube. Just like GameCube, you can use this constant that just spins at a constant rate and ensures the data so it doesn't speed up or slow down.

Dreamcast versus other consoles. PS1 was two times. PS2 was four times. Xbox was 2 times. PS2 was 4 times. Xbox was 5 times. And Y12 times for the Dreamcast. Data transfer ensured the game wrote quickly.

Cost and durability kept the drive reliable and affordable. So that's some discs there. We did Sega. Tomorrow I'll probably pick up with, we'll try original Xbox tomorrow.

Alright, well see you guys. Have a good night and I'll talk to you soon. Alright, bye.