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To the parents or teachers: How do you teach kids to program these days? 🤔
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@lyse@lyse.isobeef.org hey pascal bro! My first coding class was with an old Borland Turbo Pascal. I made my own little window manager for the assignments for class.
The teacher didn’t appreciate it much since I had to print out the code to turn it in. My Yatzee game was a stack of pages. 🤪
Today’s Advent of Code puzzle was rather easy (luckily), so I spent the day doing two other things:
- Explore VGA a bit: How to draw pixels on DOS all by yourself without a library in graphics mode 12h?
- Explose XMS a bit: How can I use more than 640 kB / 1 MB on DOS?
Both are … quite awkward. 😬 For VGA, I’ll stick to using the Borland Graphics Interface for now. Mode 13h is great, all pixels are directly addressable – but it’s only 320x200. Mode 12h (640 x 480 with 16 colors) is pretty horrible to use with all the planes and what not.
As per this spec, I’ve written a small XMS example that uses 32 MB of memory:
https://movq.de/v/9ed329b401/xms.c
It works, but it appears the only way to make use of this memory is to copy data back and forth between conventional memory and extended memory. I don’t know how useful that is going to be. 🤔 But at least I know how it works now.
It is a pleasure to work with the help system of Borland’s Turbo C++ 3.0 on DOS. The descriptions are clear and concise. There are short and simple examples. Pretty much every help page is cross-refenced and those links can be clicked.