MSX Hobby

Um site para se divertir com eletrĂ´nica

The Project

After Internet birth we have access to many documents that had previously been treated as top-secret, rare and expensive. In possession of them I studied the electronic guts of the MSX and saw that there was nothing complicated in those devices (cartridges, drive interfaces, megaram, mapper …) that were sold.

So, I had an idea after seeing schemes of 2+ Japanese. They have a chip called MSX Engine, which combines many components into a single logical device (PPI, PSG, Mapper, expander slots, etc). I will create a board with my own engine.

The block diagram below shows what is the idea. I using an Altera CPLD to recreate a simple upgrade kit for MSX 2+.

Click to view.

Some will ask me, why are you doing this if there is already one-chip MSX? I answer as follows: the implementation of the One-Chip is a huge kludge. They took several non-optimized implementations of components and included in an FPGA.

The V9938 does not have it implemented a 100% result, the USB reader does not work, the clock does not record the date and time, and some other little things I do not remember now. It’s a cool project but needs to be improved.

My project will have on a board:

  • Yamaha V9958 + 128 kB DRAM;
  • Memory mapper controller, 1 MB SRAM;
  • MegaRAM Controller 512 kB;
  • Two slot expander;
  • RTC with RP5C01;
  • Latch F4 do 2+.

Leave a Reply

Your email address will not be published. Required fields are marked *

8 − 1 =