Konami Sound Cartridge

The Konami Sound Cartridge is supplied with the MSX video games Snatcher and SD Snatcher. Sometimes it is known as the SCC+. It includes a slightly improved Konami SCC sound chip and 64kB of volatile RAM. It is likely that the RAM was included since most MSX computers in Japan at the time of release had very little memory (mostly 64kB).

Like the normal SCC, the chip has 5 audio channels. The waveform is set by 32 bytes of 8 bit samples. Each channel has its own 32 bytes of waveform, unlike the SCC where channel 4 and 5 share the waveform.

The cartridge included with Snatcher is different from the one included with SD Snatcher, but only in memory layout. It was probably done to make it incompatible. Some MSX emulators emulate this cartridge, MESS and OpenMSX for example.

Most video games on the Konami Games Collections for the MSX can use the cartridge that is included with Snatcher for better sound. Apart from those the Sound Cartridge is not used by any other programs.

The print on the chip is: KONAMI 052539 SCC-I2312P001 JAPAN followed by a fabrication location/date number, like 8951EAI. The first two digits are the year, followed by the week. The letters after that are some location/lot code.

It is possible to expand the memory to 128kB by adding 64kB of RAM to the cartridge. There are two open places on the PCB. When the RAM is added, both types of cartridges become functionally identical. The cartridge will work with both the SD Snatcher and Snatcher video games.

Surprisingly enough, a cartridge with 128kB RAM can behave exactly like a SCC ROM cartridge of 128kB. This means you can load those games into the RAM (e.g. Gradius 2, F1 Spirit, Quarth and so on) and it will behave like the original ROM cartridge until the power is turned off, since it is volatile RAM. It is possible that this chip was originally developed for internal development and testing use at Konami.

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