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.
Let’s Code MS DOS 0x29: Extended Memory XMS
In the previous episode we learned how to use Expanded Memory even down to the original IBM PC. From the IBM AT and other 286 machines onwards we can use Extended Memory instead. It doesn’t require any additional hardware and allows you to use more than 640K of memory in real mode MS DOS programs.
Commodore PET: 40K RAM with SoftROM
The Commodore PET was one of the first true PCs. The entry model PET 2001 in 1977 came with 8K of RAM. My own PET 3016 from 1979 came with 16K, which I upgraded a while ago to 32K of RAM. This lets us run a lot of software, even interactive fiction games, for example Planetfall and Zork by Infocom. However we can do better! Using the SoftROM expansion we can add an additional 8K of SRAM to our system, that can be used by the Infocom interpreter, or any other software that knows about it and is changed accordingly.