Konami SCC

The Konami SCC (Sound Custom Chip or Sound Creative Chip) is a custom sound chip that was developed by Konami with Yamaha. It is one of several sound/memory management chips Konami developed in-house that ended up in use in home computer and video game systems from the late 1980s into the 1990s until the fourth generation systems were prolific.

The chip was used to expand the sound capabilities of the MSX home computer. Its standard sound chip was a tone generating PSG, capable of 3 channels of square wave tones. As the computer used cartridges to run software such as video games, Konami placed the SCC chip onto the same board as the ROM inside the cartridge they produced. This added 5 more channels which could be used in conjunction with the sounds of the PSG. Moreover, these channels had programmable waveforms so it expanded the tonal palette of the MSX.

Konami also found use for the chip in arcade boards of the time period as well, such as the Konami GX400. The game City Bomber and others ran on this system.

On each SCC the following is printed: KONAMI 051649 2212P003 JAPAN, followed by a fabrication location/date number, like 8750EAI. The first two digits are the year, followed by the week. The letters after that are plant code of chip manufacturer (EAI is the factory code of one of Toshiba's semiconductor plant.)

Unlike the PSG which can only generate square waveforms, the SCC is a simple wavetable sound chip. The chip has 128 bytes of memory built in, combined from 4 wave samples of 32 bytes each. Each of 3 channels gets its own sample, and channels 4 and 5 share a sample. Each channel can be controlled by an on/off bit, volume, and frequency. SCC sounds can also be used together with PSG sounds.

Though 32 bytes at most resolutions does not represent a complicated sample, such as a guitar recording, the 32 bytes were usually used to construct synthetic instruments with waveforms far more complex than what the PSG tone generators could produce.

It also had a memory mapper built in, so the cartridges only needed this chip and the actual ROM. Only a few of the MSX/MSX2 games used this chip. The first of all was Gradius 2. Games like Gradius or Yie-Are Kung-Fu were produced using the PSG sound chip but they were re-launched using the SCC chip improving their sound quality.

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