Search found 173 matches

by notaz
Mon Nov 06, 2017 1:56 pm
Forum: Super 32X
Topic: "The Question" ported to 32X
Replies: 19
Views: 627

Re: "The Question" ported to 32X

Chilly Willy wrote:
Sun Nov 05, 2017 5:50 pm
EDIT2: The current NeoMyth menu mirrors rom data to make certain games work that expect mirroring.
Could you share an example of such a game?
I'm not aware of any games that are relying on mirroring.
by notaz
Sun Oct 01, 2017 11:03 pm
Forum: Video Display Processor
Topic: vcounter corruption
Replies: 1
Views: 155

vcounter corruption

I don't remember if this has been reported, but if you read the vcounter at the moment it's changing (presumably?), you'll get a corrupted value. Usually bit1 is set when it shouldn't be, at least on my VA6 MD1. It's very rare, but if you do reads in a tight loop, you'll get up to several bad reads ...
by notaz
Wed Sep 20, 2017 7:48 pm
Forum: Megadrive/Genesis
Topic: Undefined behavior for ABCD and SBCD
Replies: 32
Views: 4099

Re: Undefined behavior for ABCD and SBCD

Small update to flamewing's test to trigger a bug in Genesis-Plus-GX at least:
https://github.com/flamewing/68k-bcd-ve ... e3afd720bf
http://notaz.gp2x.de/md/rel/bcd-verifier-u1.zip
by notaz
Wed Sep 13, 2017 9:46 pm
Forum: Megadrive/Genesis
Topic: M68k opcode sizes test ROM
Replies: 19
Views: 1023

Re: M68k opcode sizes test ROM

r57shell wrote:
Wed Sep 13, 2017 3:09 pm
Here is test new version: http://www.mediafire.com/file/jl2227tc4 ... s_test.bin
Tell me if it fails or success.
It's fine now on MED but on raw flashcart it still black screens ~80% of the time.
by notaz
Wed Sep 13, 2017 2:37 pm
Forum: Megadrive/Genesis
Topic: M68k opcode sizes test ROM
Replies: 19
Views: 1023

Re: M68k opcode sizes test ROM

I'd say there is no benefit of handling warm boot differently in a test like this, unless you want to also test effects of reset.
by notaz
Sun Sep 10, 2017 8:47 pm
Forum: Megadrive/Genesis
Topic: M68k opcode sizes test ROM
Replies: 19
Views: 1023

Re: M68k opcode sizes test ROM

Yes it's a proper German MD1: http://notaz.gp2x.de/img/hw/megadrive_model1.jpg Note that I also have MegaCD + 32X attached, I know those have effect on open bus at least. The purple screen is on a Mega Everdrive v1, consistently getting it every time on the same spot. I haven't seen any other proble...
by notaz
Sun Sep 10, 2017 2:45 pm
Forum: Megadrive/Genesis
Topic: M68k opcode sizes test ROM
Replies: 19
Views: 1023

Re: M68k opcode sizes test ROM

The purple screen means failure, right?
This is what I get on my PAL MD with Hitachi 68k:
http://notaz.gp2x.de/img/mess/megadrive ... _sizes.jpg
by notaz
Tue Jun 13, 2017 3:52 pm
Forum: Collaboration
Topic: dragonbox.de cartridge production service
Replies: 4
Views: 326

Re: dragonbox.de cartridge production service

themrcul wrote:With the custom cart you are developing, I assume it will have save capability in it? And what is the largest ROM size you are targeting? (hopefully 4MB will be enough for this project).
Yes, 4MB with saves is the goal.
by notaz
Mon Jun 12, 2017 8:56 pm
Forum: Collaboration
Topic: dragonbox.de cartridge production service
Replies: 4
Views: 326

dragonbox.de cartridge production service

In support of homebrew development, dragonbox.de is announcing cartridge production service. The set includes: the PCB (up to 4MiB, currently the one from krikzz , but custom one is in development) plastic shell for the PCB (black or transparent) with a sticker instruction manual paper box packaging...
by notaz
Sun Apr 23, 2017 4:55 pm
Forum: Demos
Topic: Star J - new SHMUP for Genesis
Replies: 17
Views: 2051

Re: Star J - SHMUP in development

MD1 VA6 TMSS with all addons here, but not much time, so could run your (or anyone's) stuff once a week or so...
You may want to try sega-16 or everdrive forums to find someone more dedicated.
by notaz
Tue Apr 18, 2017 10:40 pm
Forum: Demos
Topic: OVERDRIVE II
Replies: 28
Views: 2596

Re: OVERDRIVE II

http://notaz.gp2x.de/img/hw/megadrive_model1.jpg http://notaz.gp2x.de/img/hw/megadrive_model1_case_back.jpg (with MED + both addons attached) Just like the demo itself warns, some plane glitches on "where is she" and few other scenes. Other than that, really enjoyable demo, much appreciated! Thanks ...
by notaz
Wed Apr 06, 2016 2:20 pm
Forum: Hardware
Topic: Networked Genesis hardware
Replies: 4
Views: 1036

Re: Networked Genesis hardware

I don't think this can work, the machines will desync eventually because of oscillator variations and no game hacks will be able to compensate it. There is also a problem of not fully defined state the machines start in and you'll get a desync at the very start of the game.
by notaz
Thu Jun 25, 2015 3:43 pm
Forum: Blabla
Topic: "Still Alive" (Sega-to-Sega communication) demo
Replies: 3
Views: 1831

The I/O ports have 7 pins which can be programmed as input or output, so it's possible to program any protocol you like to exchange data between the machines or even PC parallel port. The achievable bitrate is in tens of KiB/s.
by notaz
Wed Jun 10, 2015 4:44 pm
Forum: Hardware
Topic: I/O Ports read upper byte
Replies: 1
Views: 1534

IIRC it's just mirrored, it's also documented in gen-hw.txt
by notaz
Wed Jun 10, 2015 4:42 pm
Forum: Megadrive/Genesis
Topic: MOVM.L syntax
Replies: 4
Views: 1254

Why not just use as --register-prefix-optional ?