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Hello comrades! We’re back with yet another devlog! Let’s dive in so I can get back to programming!

Memory Control (Not 1984 Style)

A bit ago, I mentioned that since cartridges were physical pieces of hardware, they could have logic chips of their own controlling their own RAM, so I would have to emulate those on top of the functionality of the actual GameBoy’s hardware.

The next MBC (memory bank controller) to emulate was MBC2. MBC2 is weird. It has ROM banks as standard, but it also has 512 half-bytes of RAM built straight into the MBC chip for some reason. Those were a little weird to emulate, but altogether straightforward. I also had duplicated RAM indexing logic for both reading and writing to the cartridge RAM, which I marked todo in my code, so I had an excuse to do a quick refactor.

After handling the weird little freak that is MBC2 was implementing No MBC. You may be asking, V, what’s there to emulate if there is nothing to emulate? And to that I say, it is once again weird and silly, just how we like it. Even if a game has no MBC, it can still have some RAM; it’s just always on and has no logic for accessing it. It ended up with me having to deal with a lil extra changes to handle some things I was not anticipating.

Looks Like You’re Trying to Kill a Stick Figure

A while ago, I watched a prime video (who was also the source of the idea for this project) about the Power of 10. I’ve since thought these rules are pretty neat and can serve to make code better (with possibly the exception of rule 7). I decided that I wanted to follow rule 10 for my code, so I foolishly set all lints to max pedantic, thinking I would have some lints, but I ENDED UP HAVING HUNDREDS OF MOSTLY USELESS LINTS, many of which ended up being me using as for casting causing less readable behaviour. Some of them were useful, such as me allocating MASSIVE arrays on the stack, even if they were boxed. Turns out Box::new([0; 0x20000]) creates the array on the stack first before memcopying to the heap in unoptimised builds, which is completely unnacceptable. Also, may of my other arrays were just straight up massive and unboxed, like the framebuffer or bus memory flat array.

Anyways, after spending the bulk of this devlog’s time dealing with that, I gave up knowing the rest of the lints were harmless and pointless and clogging up important lints.

In other news, despite listening to Jamie Paige for many hours this weekend, I still ended up needing my fren to tell me about it’s new song with Vane Lily and Yuma. I also showed them to Developer theme and it brought them some joy. I’m also very happy I got the thermometer question right, especially since I have an infrared thermometer on my desk and I had to find the correct emissivity setting to use on milk yesterday since my dad was making yoghurt. Anyway, I’ll end this before Grammarly shows me any more lints for this devlog.