u/RSS130871

This is not a bitmap screen. The picture is built entirely from redefined 6×8 character glyphs in 40-column SCREEN 0.

Just because we can...!

Hi!
I just wanted to show a piece of PixelArt that I created today.
It's for the MSX1 system of the early 1980's.
There are some interesting graphics limitations like there are only 2 colours available in every 8 pixels. It's what makes pixelart a challenge!

Picture 2 shows the tool I used: a homebrew EXCEL sheet...

For those wondering what kind of tool I used for the pixelart: EXCEL!!!
There's a macro in there that exports the picture into three linked BASIC programs, that once run create a 16kb binary file that you can BLOAD straight into VRAM...

I sat down today to do some pixelart.
What do you guys think...?

After many months of development, Cloaca Maxima has reached the point where I need to stop being its developer for a while and let some other people try to break it.

For those who haven't followed the project: Cloaca Maxima is a first-person dungeon crawler for the MSX1, set beneath Rome in 114 AD.

You control four characters exploring the ancient sewers. One character acts as the Scout and encounters whatever is waiting in the next chamber first. You then have to decide whether the Scout can deal with the situation alone, or should fall back and let the rest of the party handle it.

There is exploration, combat, individual inventories, equipment, healing, permanent character death, a context-sensitive command system, save/load, and a rather large sewer system to get lost in.

And at this point, the game itself is finished.

What I need now are a few people willing to seriously TEST it.

I'm not primarily looking for impressions such as "looks cool!" — although those are always appreciated. ;-)

I'm looking for people willing to actually play the game and report things such as:

• bugs, crashes or situations where the game gets stuck;
• commands or controls that don't behave as expected;
• confusing parts of the interface or manual;
• balancing problems;
• situations where the player can accidentally make the game unwinnable;
• and, of course, anything I simply didn't think of.

You do NOT need to be a programmer. In fact, I'd very much like some testers who approach it simply as players.

The game comes with a full manual, and I would particularly like to know whether somebody can sit down with the game and that manual without me explaining anything and figure out how everything works.

Hardware testing would also be extremely valuable. Most of my development and testing has necessarily been done using an emulator, so people willing to run it on actual MSX hardware are particularly welcome.

The current build is essentially feature-complete; sound effects are the remaining TODO. This is therefore not an early alpha test. I'm looking for people willing to test something that is supposed to be a finished game — and tell me where it isn't.

If you're interested in seriously testing the game, please send me an email at rss130871@gmail.com.

I'll send you the current .DSK file and the full game manual, together with some brief information about what kind of feedback would be most useful.

You can test on an emulator or real MSX hardware — both are useful, although hardware testing would be particularly valuable.

And yes:

Please try to break it.

Hi!

After months of development, my game Cloaca Maxima is now at a checkpoint worth sharing: the engine is done.

All the major systems are working: the parser, combat, storytelling and graphics.

Now it's down to sound design and making sure nothing breaks under stress.

I've been quiet because the hard part is in the details. But I'm pleased with where it's landing, and been busy testing this last week.

Serious playtesters wanted in a few weeks...!

More details soon.

Ron

Continuing the PSG sound-design deep-dive for Cloaca Maxima.

Last time I focused on Register 13 (“Volume over Time”), which controls how sounds fade, pulse and evolve.

This time I dug into Registers 0..5: the actual TONE generators.
What started as a simple question (“how does the PSG represent musical notes internally?”) quickly turned into a fascinating little hardware archaeology project.

The key realization is that the MSX PSG does NOT store frequencies directly. Instead, it stores timer divisions called “periods”, split across two registers (“fine” and “coarse”) to form a 12-bit value.

So the process becomes:

NOTE → FREQUENCY → PERIOD → REGISTER VALUES

The attached charts show:

• the frequencies of musical notes,
• how these translate into PSG periods,
• and finally how those periods are split into actual SOUND register values.

I'm curious, is this kind of post interesting...?
Let me know!

Greetings, Ron.

P.S.: I hope this answers your question, u/riotinareasouthwest

I'm currently working on the SOUNDSCAPE for Cloaca Maxima.

First things first: there will NOT be in-game music.

Partly because of memory limitations on a stock MSX1, but mostly because it simply wouldn’t fit the atmosphere. There’s no marching band accompanying four terrified Romans into the ancient sewers beneath Rome.

What will be present are sound effects:

• dripping water,
• distant gusts of wind,
• metallic grates,
• footsteps,

To achieve this, I’ve started diving deep into the MSX PSG (Programmable Sound Generator), and honestly: the existing documentation is REALLY sketchy. Most references describe the hardware electrically, but not acoustically — meaning they tell you what the bits do, but not what you actually hear.

So I decided to reverse-engineer the envelope system myself by experimentation, and create practical reference material for future sound design work.

Turns out the PSG’s “waveforms” are not really waveforms at all, but changes in VOLUME over time.

The result is the documentation shown above: a more human-readable interpretation of PSG Register 13 and the envelope timing system used by Registers 11 and 12.

As always: let me know what you think. Especially since this is not the usual DEVlog fare, but more of a technical deep-dive into the MSX PSG itself.

Greetings, Ron.

When development started, Cloaca Maxima was intended to be a dungeon crawler. Four characters, one sewer system, one mission.

The mission is still there. So are the sewers.

But somewhere along the way, the game found its story.

The four operatives Rome sends below the city are not heroes. They are expendable. Assembled from the compromised, the coerced, and the desperate. Each of them carries a history that Rome would prefer forgotten. Each of them sees the tunnels differently.

That difference is now at the heart of the game.

Cutscenes (short text scenes triggered by exploration and discovery) are told from the perspective of whoever is currently scouting ahead. Find the same object with a different scout, and you find a different story. The same tunnels. The same darkness. Four different ways of moving through it.

No moral lectures. No easy answers. Just four people descending into something Rome sent them to destroy, carrying everything they know.

Some of them may begin to wonder if Rome was right.