Search found 744 matches

by TmEE
Wed Dec 18, 2019 12:09 am
Forum: Other Retro Dev
Topic: I am a turncoat. A simple sprite demo for Sega Master System
Replies: 44
Views: 11452

Re: I am a turncoat. A simple sprite demo for Sega Master System

tepples wrote:
Tue Dec 17, 2019 9:51 pm
periodic noise
It shouldn't be called as such, it is 6.25% duty cycle square wave on VDP PSG (SMS and MD) and 6.666...% on real TI chips.
by TmEE
Tue Dec 17, 2019 8:37 pm
Forum: Other Retro Dev
Topic: I am a turncoat. A simple sprite demo for Sega Master System
Replies: 44
Views: 11452

Re: I am a turncoat. A simple sprite demo for Sega Master System

Ohh hey. That's pretty interesting. Do emulators get this right? Not that I know of, maybe Emulicious does since it tries to be the most accurate SMS/GG emulator but I haven't looked in any detail for a long while now... The difference is very small and probably makes no visual difference, unlike M...
by TmEE
Tue Dec 17, 2019 5:47 am
Forum: Other Retro Dev
Topic: I am a turncoat. A simple sprite demo for Sega Master System
Replies: 44
Views: 11452

Re: I am a turncoat. A simple sprite demo for Sega Master System

I haven't found SMS to be painful on any regard, the hardware is really straightforward... As far as the color goes, SMS output is not linearly spaced though the difference is quite minor. +--------------------+---------------------+--------------------+ | SMS1 (315-5124) | SMS2 (315-5246) | MD (all...
by TmEE
Mon Nov 11, 2019 4:00 am
Forum: GBDev
Topic: Latching the Real Time Clock (RTC) in MBC3
Replies: 13
Views: 4018

Re: Latching the Real Time Clock (RTC) in MBC3

The metastable state cannot generally pass a clocked register and will stabilise between the clocks, but in a sausage of combinatorial logic you could have a row of gates that are all in their linear region with essentially undefined state.
by TmEE
Sat Nov 09, 2019 6:55 am
Forum: NES Graphics
Topic: NES Graphics Issues
Replies: 3
Views: 2883

Re: NES Graphics Issues

This sounds like a bad PPU.
by TmEE
Sun Nov 03, 2019 6:16 pm
Forum: General Stuff
Topic: Comix Zone: most technically impressive "16 bit" game?
Replies: 50
Views: 32842

Re: Comix Zone: most technically impressive "16 bit" game?

Only way to change sprite cache contents is to write to sprite list in VRAM, it doesn't get corrupt on its own. Line buffer and the render evaluation/preparation data retains its previous state aswell when rendering gets disrupted and things carry on where they left off when process is allowed to co...
by TmEE
Sat Nov 02, 2019 9:40 pm
Forum: General Stuff
Topic: Comix Zone: most technically impressive "16 bit" game?
Replies: 50
Views: 32842

Re: Comix Zone: most technically impressive "16 bit" game?

There's 18 access slots per line when rendering is not disabled in H320 and 16 when in H256, but you are stalling the CPU when trying to use them all since FIFO will not be emptied fast enough in most cases. If you manage to pepper some processing between the data writes you might be able to get by ...
by TmEE
Sun Oct 20, 2019 1:58 am
Forum: Other Retro Dev
Topic: Michael Abrash's VGA ModeX in Large Memory model
Replies: 20
Views: 8569

Re: Michael Abrash's VGA ModeX in Large Memory model

What is your target hardware ? 486 with ISA video will be pretty slow no matter what and some ISA video cards are *very* slow, i.e in a game like Doom which doesn't do much video related stuff can slow down 50% even when comparing slow (some OAK or Trident 9000 card) vs a fast one (Tseng ET4000, WD9...
by TmEE
Fri Oct 11, 2019 6:44 pm
Forum: SNESdev
Topic: How do emulators emulate CPU and SPC700 communication?
Replies: 4
Views: 4724

Re: How do emulators emulate CPU and SPC700 communication?

More like SPC is run from one CPU access to the next which would be much more effective, with occasional timeout catchups to prevent too large processing spikes and be ready with sound for say the current frame/end of sound buffer or something. SPC cannot really do anything to outside world outside ...
by TmEE
Sun Sep 29, 2019 2:52 pm
Forum: General Stuff
Topic: Laptop Buying
Replies: 24
Views: 15627

Re: Laptop Buying

Dells are still falling apart. I just recently worked on broken hinge attachments of a Dell laptop that was only few years old. Metallized plastic pieces caused a short on the mobo too, luckily non fatal one. A friend of mine got a brand new Dell some weeks ago and it was DOA, went to warranty and g...
by TmEE
Fri Sep 27, 2019 6:20 am
Forum: Other Retro Dev
Topic: about paprium
Replies: 13
Views: 10486

Re: about paprium

32X doesn't pass top slot !DTACK and that's why SVP/Virtua Racing doesn't work, a simple mod will restore compatibility.
by TmEE
Mon Sep 09, 2019 3:03 pm
Forum: SNESdev
Topic: Questions about SNES programming
Replies: 27
Views: 16468

Re: Questions about SNES programming

Most/all SNES games compress their GFX, there's no CHR-ROM that necessitates uncompressed GFX as on NES or NeoGeo. You could think of SNES and most other machines as NES with exclusive CHR-RAM and to save space games compress as much of their things as they can.
by TmEE
Thu Sep 05, 2019 8:53 am
Forum: phpBB Issues
Topic: 500 internal server error when posting
Replies: 34
Views: 35729

Re: 500 internal server error when posting

I experienced some inaccessibility too earlier today and yesterday evening.
Posting also produces the gateway timeout error after a while, the post itself always gets sent though.
by TmEE
Wed Aug 28, 2019 1:37 am
Forum: General Stuff
Topic: Identify CPU architecture for old EPROM that I dumped
Replies: 2
Views: 4411

Re: Identify CPU architecture for old EPROM that I dumped

it looks like Z80 code indeed, and there's a little stub at $0066 where Z80 has its NMI location.
by TmEE
Mon Aug 26, 2019 6:08 am
Forum: General Stuff
Topic: Can SMPSs damage retro consoles?
Replies: 7
Views: 4889

Re: Can SMPSs damage retro consoles?

This is a good article to read on the matter : http://sound-au.com/articles/external-psu.htm