Writing Atari 2600 and 7800 ROMs in Rust. Not a normal day.

@h0ffman Hi! Did you release any of your Musicline modules besides 'Harmonic Disorder'?

I've update the "Creating Screenshots" page on the Gopher2600 project wiki. The old page was a little out of date and included screenshots from an older version of the emulator.

https://github.com/JetSetIlly/Gopher2600-Docs/wiki/Creating-Screenshots

I'm very happy with how it's looking at the moment. I really like the method for capturing "flicker" ROMs in particular.

What I need now is a good way of producing a glass screen effect.

Playing Project Gotham Racing on the #xbox 🚗 I love how each car has a working odometer. I've played a lot of racing games but I've never noticed that before 👀

Pereelous

Really cool one! :0)
First time I see #roguelike & #slots
I love both..

https://pierre-vandermaesen.itch.io/pereelous

#gaming #games #videogames #videogamaming #gamedev #indiegamedev #rpg #rogue #roguelike #slotsmachine #slots #itchio #retrogaming #retrocomputing #pixelart #digitalart #nowplaying

Pleased to figure out what was wrong with Pole Position 2. #atari7800

The way I was dealing with display lists meant I was missing the very first interrupt at the beginning of the screen. Doh!

There's still an error if you look closely but I reckon I know what that is

This wasn't easy to get right. So I'm posting it as a celebration of a successful day #atari7800 #robotron

Watching this video of a man painting The Hay Wain (it's not John Constable). The following caught my attention. He's painting the sky and trying to match get "the Value right". I know what he means but I would have sworn this was a computer science term - as in Hue, Saturation, Value - I had no idea a regular painter would use those terms. https://youtu.be/CZNbADopjhE?t=252

Finally settled on a colour generation solution for Gopher2600. It's not perfect but it's good enough for now 🎉

https://github.com/JetSetIlly/Gopher2600/releases/tag/v0.40.0

The goal was to emulate the "colour delay potentiometer" in the #atari2600 while also allowing for the display of the 'standard' palette that people have to expect.

The solution is a compromise but I think it's acceptable.

The latest chapter in this saga is on the Gopher2600 blog.

https://jetsetilly.github.io/Gopher2600-Blog/posts/improving-the-ntsc-colour-model/

New PC build planned. This 10 year old potato won't cut it any more #Oblivion

I have a bug in my ARM FPU emulation and I have no idea what's causing it. I've picked the code apart and I see nothing wrong. It's exceedingly frustrating.

The kind of rubbish produced by ChatGPT. #AI #chatgpt

@twitnews Give enough monkeys a typewriter, one of them will eventually write, "Hey Hey We're The Monkees"

Asteroids screen corruption fixed by ZackAttack (from AtariAge). Simple once you know the solution - I was miscounting addresses when a mixture of 4byte and 5byte DL headers were being used. Required a proper #atari7800 programmer to spot 🙂

I've also added sound 🎶 I'm having difficulty keeping the sound buffer full so it sounds a bit ropey. But it's good enough for testing purposes.

#atari7800 I've managed to get Asteroids running from the PAL BIOS. I've put basic joystick support in there too so it's possible to play 🕹️

I don't know what's causing the corruption at the top of the screen though, which is shame. That's a job for tomorrow.

Not correct yet obviously but I've solved the problem relating to display list interrupts, at long last #atari7800

After the BIOS initialisation, the interrupt level was ever increasing and rarely reached the RTI instruction

The problem was caused by DMA taking too long to complete

I thought DMA was active until the end of a scanline but it will in fact end after the last DL. An early end releases precious CPU cycles for the interrupt

I'd been stuck on this for a while. Progress 🎉

Today, I have been mostly playing Injustice 2 and Spiritfarer.

First results from a test #Atari7800 emulator. This is just a basic 160A mode with indirect graphics data so nothing out of the ordinary just yet.

I'm a bit confused about Kangaroo mode. It looks to me like the display lists in the cartridge have it enabled but the results are wrong if you apply the mode as described in the literature. So I've ignored it for this video.

Pleased with the progress so far #emulation

@Richard_Littler Best episode of Mr Benn was when he tried out being a Judge in Mega City One

The test #atari7800 emulator is showing signs of life!

The video shows the loading process of a demo ROM that then runs using graphics mode 160A. For comparison, the second ROM runs using graphics mode 160B.

The DLL and DL processing is done and the 160A/B modes are the two most useful. All the other components (TIA and RIOT) are written.

The exciting moment will be when I add my ARM emulation to the emulated cartridge port. That'll be magic! 💫