Truly you are living the dream. Keep up the good work!
Search found 197 matches
- Sun Aug 11, 2019 7:50 am
- Forum: Megadrive/Genesis
- Topic: I'm officially building a microcode-level 68000 core
- Replies: 52
- Views: 143861
- Fri Jun 14, 2019 3:02 am
- Forum: Megadrive/Genesis
- Topic: Designing a cooperative-threaded scheduler for an emulator
- Replies: 14
- Views: 37895
Re: Designing a cooperative-threaded scheduler for an emulator
I have never done low level programming and I'm completely out of my depth here, but one time I contemplated, just for the sake of argument, how emulating a multiple devices down to a cycle could work... Very possible that I'm completely wrong here, but couldn't you keep an array of variables in a c...
- Mon Jun 10, 2019 8:46 pm
- Forum: Mega/SegaCD
- Topic: Japanese MegaCD BIOS 1.00C
- Replies: 1
- Views: 12263
Re: Japanese MegaCD BIOS 1.00C
I remember seeing that "pre-retail" unit. Glad to see the boot rom got dumped! It also predates the official rom identification number (not marked as EPR/MPR-14088x). For the record, EPR-14088B - ver 1.00g EPR-14088C - ver 1.00l EPR-14088D - ver 1.00o EPR-14088E - ver 1.00p MPR-14088H - ver 1.00S Th...
- Tue Jun 04, 2019 7:55 pm
- Forum: Mega/SegaCD
- Topic: Bike shedding a new CD-ROM format
- Replies: 20
- Views: 90980
Re: Bike shedding a new CD-ROM format
As I recall some PC protections used purposefully bad sectors, which got automatically "corrected" when dumping them. I don't remember the details, but this may be a problem if you decide to not store ECC. I should note that if you use the disc, or mount an image with the intact subcode data of a CD...
- Mon Jun 03, 2019 10:58 pm
- Forum: Mega/SegaCD
- Topic: Bike shedding a new CD-ROM format
- Replies: 20
- Views: 90980
Re: Bike shedding a new CD-ROM format
It's true that subcode can be generated, but if you generate them, why even bother trying to read them? And if you *assume* how the format looks based on the rules, then you'll overlook discs which do not confirm to those rules. Not that I can name any from the top of my head, but if we are using cl...
- Mon Jun 03, 2019 8:47 am
- Forum: Mega/SegaCD
- Topic: Bike shedding a new CD-ROM format
- Replies: 20
- Views: 90980
Re: Bike shedding a new CD-ROM format
Subcode reading is dodgy, even on the best drives. That is, you can't rip two of the same discs to identical CRCs.
- Sat Jun 01, 2019 6:20 pm
- Forum: Mega/SegaCD
- Topic: Bike shedding a new CD-ROM format
- Replies: 20
- Views: 90980
Re: Bike shedding a new CD-ROM format
This would be great, but what exactly would you use to rip in these formats? They are kind of pointless if nothing can create them. Don't forget that most data you want to rip is "unrippable" due to not only damage to the CDs, but also due to defective duplication, mastering errors, etc. There's a r...
- Sat May 18, 2019 9:20 pm
- Forum: Mega/SegaCD
- Topic: Questions on writing a new Mega CD emulator
- Replies: 117
- Views: 10958275
Re: Questions on writing a new Mega CD emulator
Mega CD specification doc is nice. No official Saturn CD format specification around, btw? ST-040-R4-051795 and tech bulletin #7 details those. It's nothing we haven't known before, though. It mostly details things like minimum LBA, the ISO9660 filesystems, sector frame sizes - all standard CDROM s...
- Sat Apr 20, 2019 2:37 am
- Forum: Blabla
- Topic: Where is your very first Megadrive/Genesis now?
- Replies: 4
- Views: 14400
Re: Where is your very first Megadrive/Genesis now?
The first one has been sold for a Saturn a long time ago.
The second one, which is the one I bought from my own money, has been my primary unit for 20 years now. Over the years it was enhanced by a couple of mods and has been recapped.
The second one, which is the one I bought from my own money, has been my primary unit for 20 years now. Over the years it was enhanced by a couple of mods and has been recapped.
- Mon Apr 15, 2019 1:33 am
- Forum: Megadrive/Genesis
- Topic: Compiling an emulator for enhanced Megadrive
- Replies: 42
- Views: 53640
Re: Compiling an emulator for enhanced Megadrive
There's little point to the "Tower of power" when a Saturn is better for all practical purposes. Still being a Genesis is part of the constraint. How about going backwards then: making something for the Saturn to run Megadrive games ? Obviously doing it in software alone would be near insanity, but...
- Tue Apr 09, 2019 7:55 pm
- Forum: Megadrive/Genesis
- Topic: Compiling an emulator for enhanced Megadrive
- Replies: 42
- Views: 53640
Re: Compiling an emulator for enhanced Megadrive
How does the C2 have 15bit colour? I thought it just had the external palette hooked up to double the entries from four to eight.
- Tue Mar 26, 2019 1:54 pm
- Forum: Megadrive/Genesis
- Topic: Space Herrier II and The Sprite Scanline Limit
- Replies: 11
- Views: 16811
Re: Space Herrier II and The Sprite Scanline Limit
Keio Flying Squadron does something like that, using sprites as a background. At one point (around stage 5 or 6?) it has a huge Ark that splashes onto the sea and you have to catch up with it. Normally the sea takes up all the backgrounds, and once you reach the ark, it's made up of sprites only. Th...
- Sun Oct 28, 2018 9:35 pm
- Forum: MegaLD
- Topic: MegaLD Dumping Project
- Replies: 74
- Views: 434495
Re: MegaLD Dumping Project
Possibly related.
https://www.youtube.com/watch?v=klK4UZ5nlqs
https://www.youtube.com/watch?v=klK4UZ5nlqs
- Tue Sep 18, 2018 12:33 pm
- Forum: Hardware
- Topic: Some questions about Saturn HW
- Replies: 25
- Views: 44116
Re: Some questions about Saturn HW
Yeah, 14.318 / 4 = 3.579545 MHz and 17.734 / 4 = 4.43361875 MHz, the NTSC and PAL colour bursts, respectively. The PLL outputs them to the video encoder.
- Mon Sep 17, 2018 10:05 pm
- Forum: Hardware
- Topic: Some questions about Saturn HW
- Replies: 25
- Views: 44116
Re: Some questions about Saturn HW
Thanks for this complete answer ! So it could be possible to overclock the saturn but not without affecting video signal? No, the VDP2 generates the dot clock using the input clock / 4. If you over or underclock the system, it will display the wrong resolution and/or the wrong h/v sync and the imag...