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Developer: Pyhesty [RBSC]. Copyright (C) 2022
Русская версия находится здесь: MSX-EQ PSG Spectrolyzer для платформы MSX
The MSX-EQ PSG Spectrolyzer is a simple cartridge for the MSX platform that visualizes the spectrum of notes played by the programmable sound generator, such as the AY-3-8910 or YM2149 (PSG). The cartridge board is intended for the standard MSX cartridge slot. The board shows the effect of measuring the signal's level, in which each reproduced frequency (or frequency range) corresponds to one of 9 vertical LED indicators.
The MSX-EQ cartridge is based on the PLD Altera EPM7128, that has 128 logical units. The PLD intercepts PSG port I/O, identifies the played note/frequency and displays its representation on the dedicated LED indicator. The cartridge doesn't need any special setup. It can be installed into any standard MSX slot that allows an unobstructed view of the cartridge's LED indicators.
The cartridge visualizes the played notes/frequencies in games and demos in real time. After a note/frequency fades out, the LED indicators automatically switch off.
The cartridge may be assembled in 2 different ways:
The following color combinations are possible (those were tested and were found suitable for the project, however other color combinations are possible):
Лицевая сторона печатной платы:
Обозначение | Номинал/марка | Количество | Примечание |
---|---|---|---|
C1..C6 | 100nF | 6 | C0805 |
C7..C8 | 47uF 10v | 2 | CPOL-EUSMCB SMC_B |
DA1..DA9 | LEDs | 9 | 2010BB DIP-8 |
D1 | EPM7128STC100 | 1 | TSOP-100 |
R1..R37 | 1k | 37 | R0805 |
XP2 | PLD10 | 1 | PIN-10 |
MSXSLOT | EDGE-CONNECTOR | 1 | 50-pin slot |
Any factory-made MSX cartridge manufactured from semi-transparent or transparent plastic is suitable for the MSX-EQ cartridge board.
For example, the following quality MSX cartridge cases can be obtained from Overrich (South Korea) and Retro Game Restore (Taiwan):
Also, there's a 3D model of the cartridge case in the repository. The case should be printed with semi-transparent filament.
You can check how the cartridge visualizes various PSG effects by watching these videos:
All files of the MSX-EQ project are available in the RBSC's Github repository: here.
The RBSC provides all the files and information for free, without any liability. The provided information, software or hardware must not be used for commercial purposes unless permitted by the RBSC. Producing a small amount of bare boards for personal projects and selling the rest of the batch is allowed without the permission of RBSC.
When the sources of the tools are used to create alternative projects, please always mention the original source and the copyright!