A user from the DOSReloaded forum sent me his dead Roland MT-32, arguably one of the most sought after and iconic synthesizers for playing vintage DOS games. This item is said to be totally dead, no LCD display and no sound. So let’s have a look at what’s wrong and if we can fix it!
Marco Roth reverse engineered a broken M396F mainboard, powered by a 386SX CPU. This tiny Baby AT sized mainboard comes with six 16 bit ISA slots, four 30 pin SIMM sockets, a 40 MHz AMD branded 80386SX CPU and is a fancy purple color! Does it work? Let’s throw some soundcards and games at it and see how it behaves! Marco didn’t have a lot of cards to test with, so I offered to do it for him. Let’s see how it turned out!
I was asked by a viewer if the Roland SoundBrush that I showed in an earlier episode can also be used to record MIDI music from a PC. And yes of course, it can. With some caveats though! I connected the SoundBrush to my 486 PC and tried a few games. Lucasfilm games were running into buffer problems on the SoundBrush, but Sierra games were playing nicely. Let’s have a look and a listen how you can wire up the SoundBrush, format some floppies and record some MIDI files!
In this episode we learn how to program a little tic-tac-toe game for two human players. No AI, just the input and output and the winning condition! We learn different methods to compare registers and memory locations, different conditional jumps and how to save a few bytes by replacing CALL instructions with JMP.
I have a couple of broken 1541 floppy drives for the C64 and similar machines. Some have broken mechanisms, of Mitsumi variety, where the read coils are fried, but also one drive that has supposedly some PCB issues. Let’s see if we can assemble a Frankenstein 1541 drive by taking bits and pieces from each drive!
In this episode we learn how to declare variables in assembly language. Also we learn how to access data from pointers stored in registers. We learn a couple of jump instructions and how to loop. We use this knowledge to compute all prime numbers below 1000 and print them to the screen. As usual this is based on the book “Programming Boot Sector Games” by Oscar Toledo.
Last time we restored Ocarina of Time to its former glory, this time it’s Majora’s Mask. This N64 cartridge was hit by last year’s flood, which besides hurting lots of people also claimed the less important artifacts, such as retro game collections. Here we have one example of a cartridge that was salvaged by the owner, before he sold it to me, untested. Let’s see if we can clean it up and get it going!
In this episode we learn how to use the DIV opcode for dividing integer numbers, how to print integer numbers to the screen, as well as how to use a debugger to understand what our program does. In all coding tasks looking for errors and understanding what the program actually does is a key aspect. So a debugger (here we use the Turbo Debugger by Borland) is a very useful tool that every developer should know how to use.
So you always wanted a Roland MT-32. Even as a kid you saw it in ads, and in the setup programs of games. But it was way to expensive. And today you still will pay upwards of 250 EUR for a working device, which is more than 30 years old. So why not emulate it? There is now a Waveblaster compatible module that will fit on many retro sound cards and which is able to emulate the MT-32 as well as SoundFont based GM and GS compatible synthesizers.
The SEGA GameGear that we revived in the last video gets a new shell! The old one was beaten up pretty roughly. And new shells in all kinds of colours are still made to this day. At the same time I will be replacing the electrolytic caps with small SMD ones. I disliked how the electrolytics were all over the place, making the shell hard to close. However something went wrong in the end, due to my own negligence…