Archive for June, 2014
Introducing the Superboard ///. This new board is based on the Ohio Scientific Superboard II also known as the OSI 600 or the OSI C1P when installed in a case. It comes with 32K RAM, 1K video RAM, a full 53 key matrix keyboard and a USB port for loading and storing programs to a PC or Mac.
The system is based on the WDC65C02 running a 1MHz in a low power setup running at 3.3V. The video and ROM is stored in the Parallax Propeller chip and firmware updates are easy with the free Parallax programming tools included with the CD or from the Parallax web site.
Video is 25×25 with standard text and graphic characters. This character set and the video mode exactly match the OSI Superboard II and has been tested next to a working original unit for the most accurate video emulation possible. A 32×32 mode is available by simply holding the BREAK key on power up.
BREAK key: The original Superboard II had a real issue with the break key. It is located next to the return key and was very easy to press by accident. When pressed a cold RESET is performed and all data is lost! The fix was to make the BREAK key held for 3 seconds before a RESET is performed. This prevents accidental RESET of the system board and data loss.
The cassette interface section was removed and just the serial port retained. The serial port is programmed at 9600 BAUD but no handshaking is involved so delay’s are required when sending data. Still, this is faster than cassette and really a great way to load and store programs. A cassette interface may be possible in the future and all signals for making a cassette interface are on a port header.
The keyboard: This was the heart and soul of the Superboard III project. What made the OSI Superboard II so unique is that it was an all-in-one board with video and keyboard built on. The onboard keyboard really gave the board a complete system look. Thanks to WASD, we are able to have custom key caps made that closely match the original key caps. These are not pulled off some new keyboard, these are custom made caps. Pay close attention to some of the special keys like “RETURN” and “line feed” for example. The caps top off one of the industries best know switches, the Cherry MX series switches. These switches give the Superboard III that vintage feel and are actually higher quality switches then those used on the OSI Superboard II.
The USB port: This is not only a power port, but a serial communication port. Plug this into your PC or Mac and you can not only power your Superboard III from the port, but you can have transfer programs using a terminal program such as Hyperterminal, Tera Term, and ZTerm. Using the cassette interface commands LOAD and STORE activates the terminal modes and you can actually type on the PC and see the results on the Superboard III display. This allows you to send files to the System board with ease. Type STORE on the Superboard and anything that is goes to the screen, now also goes to the serial port. Use this to save programs!
Expansion: The 40 pin expansion port matches the 40 pin port of the original Superboard except an IDC header was used instead of a chip socket. This was intentional so that original boards are not just plugged in. There needs to be voltage line buffering to be compatible with 5V signals. In the near future, a buffer board will be available for those that need one.