MagicSound

At the time when people sold Covoxes and play popular ST files was born an idea to build the MagicSound board for Aleste computer. Our specifications were:

• Aleste should have unless 512 KB memory. That was typical size of ST files.
• Aleste’s expansion slot should support DMA to whole address space.
• Aleste’s expansion bus should be well buffered and have strong DMA communication.
• The soundboard should have 4 channels DMA and same number of programmed timers. It should have interrupt system for evens like: end of sample and programmable time period.
• The soundboard should have 8-bit DAC, mixer and volume control for each channel.

A lot of time we spent for design the memory management and expansion slot pinout then we spen some time for design stable DMA communication protocol. Then was madden first MagicSound board (but at this point board had no name). The DMA controller used at that board was slow and doesn’t support transfer more then 16 KB per action. It showed that idea works.

After that DMA controller was replaced to IC from i86 series and was developed good memory manager which lets to DMA IC access to whole 2 MB memory space. The first board «MagicSound» was designed and prototyped quicly, after was coded first ST file’s player.

Repository

The MagicSound's files on Aleste 520EX on GitHub

Links

CPC Wiki