I received a hand full of broken C64 machines, and am now trying to repair one machine at a time. This machine here seems to have multiple issues, but is working mostly. The color on the screen is shimmering a lot though. This might be a color RAM or PLA issue. Let’s investigate!
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Sinclair ZX81: AV mod and New Keyboard
I have acquired a Sinclair ZX81 from 1981. It is a Z80 based machine with e measly 1KiB of RAM, and arguably the worst keyboard ever. It has only RF video out, so you need a very old TV for that. We will do a composite A/V mod to have more and better options of video output, and it will require a new membrane keyboard, as those usually fail after all these decades.
Let’s Code MS DOS 0x2E: VGA Redefinable Charsets
The EGA and VGA cards support custom or redefinable character sets. Those can be used to add characters from languages not covered by the original ROMs on the card, but can also be used to aid in drawing shapes in text mode. We will use this feature to port our VGA plasma effect from graphics to text mode.
Let’s Code MS DOS 0x2D: L System XMas
It is the holiday season again, and what better way to celebrate than with MS DOS, PowerBasic and some nice L-systems! This time we introduce the push and pop functions and use them to draw colorful Christmas trees!
Pokemon Red Restoration
A very dirty and beat up Pokemon Red cartridge is on my desk today. So let’s clean it up and make it shiny!
New Atari 2600 Homebrew Games
The Atari VCS or 2600 is almost half a century old, but very much still alive and kicking! Let’s have a look at five great homebrew games from the best couple of years. And one of those games I will give away! So stay until the end of the video on how to take part.
Let’s Code MS DOS 0x2C: Noisy 3D Animation
Earlier this year I saw a demo effect using a random noise background and simple wireframe 3D using XOR line drawing to create an interesting visual effect. Building on the 3D Cube program we did a while ago we can reimplement this effect. The magic happens when you pause the animation — or this video. Then the object magically disappears…
What if the Amiga sounded better?
Back in 1985 when the Amiga came out the Paula sound chip was not totally groundbreaking, but better than most of its competitors. It supported four channel stereo PCM playback. This could be used with sampled instruments to get a relatively natural sound. However there were many limitations, many of which due to the software not utilising the Paula to its fullest. Two years later, when the A500 came out, Roland released the MT-32. A consumer grade synthesizer module that was used relatively widely in the MS DOS gaming world, spearheaded by Sierra On-Line. It is a little known fact that you can use the MT-32 also on the Amiga with Sierra adventures such as King’s Quest, Space Quest or Larry. Does the Amiga sound better with the MT-32?
Let’s Code MS DOS 0x2B: Memory and Pointers
Here is a little refresher on how memory management and pointers work in the C programming language, and especially under real mode MS DOS programs written in Turbo C 2.0. We will go back to the basics to give all the new subscribers of this video series a chance to catch up.
Let’s Code MS DOS 0x2A: Background Adlib Music
We already learned how to program the Adlib sound card to produce percussion and melodic instruments. Now we tackle the problem of getting real music out of it. By utilizing the Reality Adlib Tracker’s playback routine we learn how to program the Programmable Interrupt Timer (PIT) in the PC to get a steady playback of background music.