| RBSC group Completed projects Projects in development Licensing Other projects |
|
Carnivore2 is the multi-functional cartridge for the MSX platform that was created in 2017. The project is still supported - new firmware for FPGA Altera is being released, as well as software - the tools for working with the cartridge, the program for creating the startup menu (boot block).
The cartridge is compatible with all MSX computers from MSX1 to TurboR. In order for the cartridge to work properly on the Arabic and Korean MSX systems, the special version of the boot block and directory editing utilities are required.
iBolit is a simple diagnostics cartridge. During the last year we've seen numerous messages from MSX users, whose computers stopped working after being removed from the storage or after another power cycle. Many people complained about black screens or about total power failure. It's a known fact that RAM and other elements may go bad during storage or at power-on. Diagnosing those problems usually starts from checking the power rails, clock signals, reset signal's state and activity on data and address bus. It has been decided to create a simple diagnostics cartridge that could help to perform the initial check of a computer and rule out the most common problems.
The cartridge named "iBolit" (see Doctor Aybolit) was created using the GAL22V10 programmable logic chips, LED assemblies and volt/ammeters from the PC's USB socket tester dongles. There's an additional cartridge slot installed on the top of iBolit cartridge. There one can insert any cartridge including the one with MSX diagnostics ROM (there are a few, but it would be nice to create a universal one). The GAL firmware is very primitive — if there's a high level on input, the LED connected to the output will light up. The cartridge is fairly cheap to build — maximum 12-15 Euro and is relatively easy to assemble. The daughterboard with voltmeters is detachable.
A few photos of the board:
The drawback is that some signals switch from high to low very fast (for example CLK), so it's impossible to see distinct LED blinking for such signals - the LED will just be lit and the brightness will depend on the frequency. With the current design it's not possible to make the blinking more visible. But that's not planned. It's enough to see that there's an activity on the signal.
A few videos of prototype's test:
This project is for upgrading the Yamaha YIS-805/128R2 MSX2 and similar computers to MSX2+. The upgrade is completely reversible, with the exception of the video processor - you can return your computer to the MSX2 state any time. The new video processor is backwards compatible with the original one so you can leave it. The upgrades could be made by any user without in-depth knowledge of electronics. However, decent soldering skills are required.
This project is for the improved video module for Yamaha YIS-503 and similar computers. Unlike the original module, the improved video module has the S–Video connector and provides high quality video output in NTSC or PAL standard from the composite video and S-Video outputs.
The board was primarily designed for Yamaha YIS-503IIIR computers that do not have color output from the composite video connector. But it can be also installed in the Yamaha YIS-503IIR and similar computers to obtain better quality video from the composite video output.
This board is not suitable for Yamaha YIS-805/128R2 and similar computers!
This project is for the improved video module for Yamaha YIS-805/128R2 and similar computers. Unlike the original module, the improved video module has the S–Video connector and provides high quality video output in NTSC or PAL standard from the composite video and S-Video outputs.
The board was primarily designed for Yamaha YIS-805/128R2 computers that do not have color video output from the composite video connector. But it can be installed in other similar computers to obtain better video quality from the composite video output.
This board is not suitable for Yamaha YIS-503IIIR and other similar computers!
This combo board was designed to upgrade MSX2 computers similar to Yamaha YIS-503 and YIS-805 to MSX2+. Also, this board can be used to add the FMPAC sound card to any MSX1 and MSX2 computers.
The board contains the FMPAC sound card based on the OPLL YM2413 chip, as well as the F4 register, that is used to support the "warm boot"on MSX2+ computers. The mono sound output goes to the internal amplifier of MSX computer.
The board is inserted into the 40-pin socket that is soldered instead of the Z80 processor and the processor is inserted into the socket mounted on the top of the board.
To solve the problem of not having a disk drive on the Yamaha YIS-503 and similar computers, we have created the adapter for the GoTek floppy emulator. At the moment, the GoTek SFR1M44-U100K is the best floppy drive emulator based on its price and availability. This device was created in China, it is based on the ARM microprocessor and it works very well with Keirf's FlashFloppy firmware.
Since the side slot of YIS-503 computers is rarely used, it was decided to make the module specifically for that slot and have the GoTek emulator partially located inside that module. It is also possible to install the special cover with the floppy drive interface and power connectors instead of GoTek.
The Brazilian TDC-600 was chosen as the floppy disk controller, taking into account its simplicity and small size - there is little space left in the module's case after inserting the GoTek emulator. The controller was implemented using SMD components to save space. The connectors were chosen so that you can easily insert the GoTek emulator into the module's case, connect it to the floppy interface and power and then securely fix the emulator inside the case. The controller contains 2 different disk BIOS ROM versions - the desired version is selected with the jumper on the board.
When installed in the Yamaha's side slot, the emulator's screen ends up on the right side and is not easily visible. Therefore, we created the way to install the stationary or rotating OLED screen onto the emulator's case.
Since the OPM SFG-01 and SFG-05 sound cards were only supplied with certain models of Yamaha MSX computers and only for the use in their side slots, they did not become popular among MSX users. However, the excellent sound quality of this module, as well as the large number of music files for it pushed us to create a clone of the Yamaha SFG module.
It was decided to use the original sound chip YM2151, the YM3012 DAC (digital-to-analog converter) and the UART YM2148. But the lack of YM2148 chips on the market, as well as the complete lack of documentation for this chip, forced us to look for an alternative. As a result, it was decided to leave only the sound chip and the DAC and to put everything else in the FPGA.
The clone of the SFG module is based on the Altera Max FPGA, which includes all the logic circuits and the YM2148's emulation. The main ROM was designed to have a switch so that a user could choose which version of the firmware to use. Both versions were included - from SFG-01 and from SFG-05. We used the specially patched version from SFG-05, which allowed the module to work with the older YM2151 chip. We also used different amplifiers - the LM4558s.
The MIDI input and output connectors' location was chosen so that it would be possible to use the cases from the original KYBT or KYBT2 network modules. In this case, the connectors for the music keyboard and stereo output should not be installed. For the SFG module with all connectors we created the special 3D model of the case.
The OPM SFG-01 and SFG-05 sound cards were shipped only with certain Yamaha MSX models and they could be only used in the side slots of these computers. For other models of MSX computers without the side slot, the SFG modules could only be used with a rather rare adapter from 50-pin to 60-pin slot (now this option is provided with our FLEX adapter). The demand for the OPM module among MSX users as well as the large number of music files for it prompted us to create the Yamaha SFG module in the form of the standard MSX cartridge.
It was decided to use the original sound chip YM2151 and the YM3012 DAC (digital-to-analog converter). Due to the lack of space for the MIDI connectors, stereo outputs and the music keyboard connector, we placed an IDC connector on top of the cartridge. It is used for connecting the special adapter board that has all those connectors. Moreover, you can connect the adapter board either directly to the top of the cartridge or use the standard IDE cable to connect the cartridge and the adapter board.
The cartridge is based on the Altera Max FPGA, which includes all the logic circuits and the YM2148 emulation. The main ROM was designed to have a switch so that a user could choose which version of the firmware to use. Both versions were included - from SFG-01 and from SFG-05. We used the specially patched version from SFG-05, which allowed the module to work with the older YM2151 chip. We also used different amplifiers - the LM4558s.
This cartridge was developed as an alternative to the existing cartridges with support for individual mappers (Konami 4, ASCII8, etc.). The idea was to create a simple, cheap and at the same time universal cartridge with support for all common mappers.
The cartridge is based on the Altera FPGA and 512 KB FlashROM chip AM29F040. The cartridge can be programmed in the MSX computer using the special FL16 utility. The selection of the mappers or the planar mode is done by jumpers. The write-protection is also enabled by the jumper.
Later we created the improved versions of this cartridge with 512 KB and 2 MB FlashROM chips and the Altera Max FPGA for commercial use. Please see the Licensing page for more info.
This device was created in parallel with the first version of Carnivore to be used with the diskless Yamaha YIS-503IIIR computers. The device has fully-fledged IDE and FDD controllers, allowing you to connect both standard 720 KB floppy drives as well as the modern 1.44 MB floppy drives to MSX. The controller also allows you to use the CF (CompactFlash) card as the removable media for the high-capacity IDE drive.
The device is based on the Altera Max FPGA and the standard floppy disk controller chip WD37C65B. The configuration jumpers allow you to prioritize the devices (FDD/IDE), as well as to select the configuration for the floppy drives. The device has a dual disk ROM selectable by jumper. You can choose either Sunrise disk ROM or Nextor disk ROM, which makes this controller versatile and easy to use.
This project was developed by a member of the RBSC Timur Tashpulatov and, according to his recommendation, was included into the "Completed Projects" section.
The main goal of this project was to connect the diskless Yamaha YIS-503IIIR MSX2 computer to a personal computer that would emulate another MSX2 computer (a teacher). With some amount of reverse engineering, programming and soldering, it will be possible to download MSX games using the built-in networking capabilities of YIS-503IIIR computers.
The device is extremely easy to build and to use and allows you to download simple games (up to 32 KB), as well as games up to 128 KB (split into several parts) from a personal computer directly into MSX. The download speed through MSX-Link is much higher than through the standard cassette interface.
The Yamaha computer's side slot was designed to connect a limited number of peripherals, for example SFG-01 or SFG-05 sound cards. In YIS-503 and YIS-805 computers that were shipped as KYBT and KYBT2 sets during the end of the last century, this slot was occupied by the network module that has not much use now. Therefore, we created the special adapter that turns the 60-pin side slot of Yamaha MSX computers into the third standard 50-pin cartridge slot. In this slot you can use the 8bits4ever's EmuFDC cartridge, as well as other simple cartridges that do not require an extended slot.
The adapter is secured in the computer's case with the screw taken from the network module (or SFG module). This is done to prevent it from being accidentally removed from the side slot when pulling out a cartridge.
BSA (Back Slot Adapter) is the adapter for the Yamaha CX5M's and similar computers' rear slot. In these computers the rear, second, slot is not usable as the standard slot for connecting MSX devices and cartridges. The BSA adapter solves this problem by providing the starndard 50-pin slot after being inserted into the back of a computer.
If you wish, you can do laser engraving with RBSC's logo and the device's name on the adapter's case.
FLEX (FLexible EXtender) is the adapter-converter for MSX slots with a flexible cable. This device allows you to connect any cartridge with the 50-pin connector as well as slot expanders to the standard 50-pin MSX slot. It is also possible to connect devices designed for the Yamaha computer's side slot to the standard 50-pin slot. This makes it possible to use the side slot devices with any MSX computer.
The FLEX set includes 3 modules:
The modules are connected with each other with the 50-wire flat cable that is approximately 30 cm long. The laser engraving with the RBSC's logo and the device's name could be done on the FLEX cases.
This adapter board was designed for upgrading Yamaha YIS-805 and similar computers. This can be either MSX2+ level upgrade or the installation of the FMPAC sound card into the computer.
Since the Z80 processor in the above mentioned computers is located under the power supply, installing the FMPAC/F4 board or the RAM expansion module is not be possible. This board was designed to transfer the terminals of the Z80 processor to a more convenient place. The adapter board is attached to the motherboard with two plastic feet. The feet are glued to the motherboard with double-sided tape, and then the adapter board is placed onto them. The adapter board is attached to the feet using two small screws. Such connection allows you to easily insert and remove upgrade modules from the adapter board.
The YM2148 microchip emulator was developed as a part of the Yamaha SFG module's cloning project. The YM2148 chips are no longer available, there is no official datasheet for them, so it was decided to replace this chip with the Altera Max FPGA based emulator.
The YM2148 emulator can be used to repair the SFG-01 and SFG-05 sound cards where this chip is damaged or missing.
Carnivore is the multi-functional cartridge for the MSX platform that was created in 2016. That was the first cartridge in the Carnivore's family of multi-functional cartridges developed by RBSC.
The cartridge is compatible with all MSX computers from MSX1 to TurboR. In order for the cartridge to work properly on the Arabic and Korean MSX systems, the special version of the boot block and directory editing utilities are required.
SGC is the cartridge for small (up to 64kb) games without mapper. The cartridge contains the Winbond W27C512 EEPROM chip, that can be programmed without being removed from the board with the special adapter board and a standard EEPROM programmer. The utility called "SGC Image Creator" can convert ROM files into the binaries suitable for programming into the EEPROM chip.
This cartridge can be licensed for commercial use. Please see the Licensing page for more info.
The Konami SCC cartridge repair board is designed to replace the broken or missing 2212P003 Konami chips. The board emulates the K4 mapper. There will be no SCC output from the fixed cartridge, so it's necessary to use an SCC-capable cartridge in another slot. The repair board supports up to 512kb EPROM chips.
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 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.
You can check how the cartridge visualizes various PSG effects by watching these videos:
The MSX Unimapper is a cartridge platform for MSX computers that separately supports 4 different mappers and allows to launch software and game ROMs up to 512kb on any compatible MSX system. The mappers are emulated by 2 or 3 programmable logic (PLD) GAL22V10 chips. Each mapper requires its own firmware to be programmed into the PLDs. The cartridge platform includes 2 different variants of the same cartridge.
UniMapper cartridge supports the following MSX mappers:
How to double the amount of floppy drives in MSX computer? DualSlim can help!
Some MSX computers have two physical floppy drives. Other, more compact computers, normally have one full-sized floppy drive. Is it possible to have two drives instead of one in those computers? But of course! With the help of DualSlim adapter board and the set of 3D printed parts anyone can install 2 slim floppy drives or a slim Gotek drive and a slim floppy drive into MSX computer.
It's a well-known fact that certain MSX2/2+ computers have a so-called "HIC Board" - the special "Hybrid IC" daughterboard that is mounted onto the MSX computer's motherboard and provides certain functionality. This functionality includes converting RGBS signals to composite video, audio mixing and pre-amplifying, muting audio on power events and so on.
Normally, the board works just fine, but there's a problem with 3 electrolytic capacitors - they leak and damage the board, sometimes beyond repair. Fixing the leaked boards is difficult as some components can separate from the corroded solder pads, some tracks may become corroded under the CXA chip, resulting in the board's malfunction.
Taking into account all the above listed problems, it was decided to clone the HIC board and at the same time add certain improvements.
The reworked version of the 1998's TESTRAM utility. The original version was created by A&L Software. The old RAM testing utility had a few problems that have been fixed in the 2.0 version. In addition, the SE (Special Edition) version has been created, this version is compatible with Arabic and Korean MSX/MSX2 computers.
Adapters for computers with front or side cartridge slots. The purpose of these adapters is to change the orientation of inserted cartridges in order to insert them vertically and to face a user. This is especially important for diagnostic cartridges (iBolit, Barmaley), cartridges with screens (EMUFDC) or for cartridges with blinking LED lights (MSX-EQ and others). Computers with front slots include Daewoo 400S, Yamaha YIS805, Sony F500, F700 or F900 and many others.
The Model A is suitable for:
The Model B is suitable for
The Model B adapter is supplied with the special bracket to activate the power switch on Sony MSX computers.
Both adapters are designed to have 2-color 3D-printed cases.
The cases have screw holes, but they are designed to be closed firmly without screws.