Vintage Ohio Scientific Challenger 1P Superboard II Model 600 6502 BASIC SBC1980
Item History & Price
| Reference Number: Avaluer:51072708 | Brand: ohio scientific |
| Vintage: Yes | Model: superboard ii |
For sale is an Ohio Scientific Superboard II, rev D, circa 1980 (Feb 15, 1980, according to a stamp on the board).
This single-board complete computer features built-in 24 line by 24 character video with NTSC composite output, Microsoft 8K BASIC in ROM, 8K of RAM (in the form of sixteen 2114 1K*4 chips). The standard installed monitor firmware allows access to machine code as well as boot to expansion floppy disk (if installed via an optional 610 expansion board). On-boar...d cassette interface (load/save) was not tested as this machine is currently configures to use RS-232 upload/download. Some traces on the board are cut and some have been re-soldered: like many computers of the day, some circuitry might well have been modified for a specific use (RAM expansion on the board, video modifications to 32 columns, or even overclocking to 2MHz). These machines were very popular with the hobbyist/experimenter crowd so many C1P's from this era have modifications of some type. Essential circuitry on this board has been restored to the original factory design. The Monitor and BASIC ROMs are Xicor 2816 2K EEPROMs (burned with firmware from the same revision board) while the character generator ROM is a factory masked 2316 type.
The video output (NTSC composite) comes via an RCA cable which mates with a connector on the board.
Testing was performed as follows:
Upon power-up (or when the reset key is pressed) the "D/C/W/M" prompt appears. Ensure the CAPS LOCK button is down and press "C" followed by ENTER several times to enter BASIC. The system shows 7423 bytes free (8K minus memory used by the system including page zero for the 6502, variables for basic, and the stack).
The keyboard was tested by pressing each key. A BASIC program was then entered via the keyboard and run (primarily to test the keyboard).
The ACIA was tested by typing SAVE then LIST at which point characters appear at the (slow) rate of about 120 per second on an external serial terminal: since the board has a built-in serial interface, the RS-232 Data Out signal on J3 (pin 2) was run to a PC running TeraTerm and characters on the screen were echoed to the terminal. No testing of the cassette port was done at all (since this would require reconfiguration of the machine ... see below ...). The connector on J3 is currently wired for serial RS-232 operation at 1200 baud but it can be wired for cassette operation (at 300 baud). Use of the serial port to upload/download programs is a more reliable method though.
The ACIA is currently configured for 1200, N, 8, 1 for transfers via the RS-232 port ... for use with the cassette port it will be necessary to reconfigure this (the cassette is hence untested). To test the machine, the on-board serial interface was wired to a PC as follows:
J3 pin 1 = Ground
J3 pin 2 = RS-232 Transmit to the PC
J3 pin 3 = RS-232 Receive from the PC
J3 pin 4 jumpered to J3 pin 6 (this is the RC Clock)
Running TeraTerm on the PC, once can transfer programs up to the OSI as follows: Set TeraTerm transmit delays for 20ms between characters and 500ms between lines (remember that this machine was designed for cassette storage at 300 baud), Type "LOAD" on the OSI, Send the BASIC program as an ASCII file from the PC to the OSI, when done type on the OSI and RUN the program. It was tested with Seawolfe by Rodger Olsen (Aardvark, 1978) - it loaded the program and ran it fine (this also allowed testing of the video memory).
The keys are raised in rows for use in a case: when I bought this unit many years ago it was in a home-built wooden case, and while I always intended to solder the keys back to their original positions flat on the board, raising the keys like this is exactly what is needed to when placing this board in a case so the keys fit the sloped front properly! The keys are mounted on a fiberglass piece with jumper wires connecting them to the main board underneath.
All keys were tested to work (see the photo of characters produced from keypresses) albeit some are a bit "sticky". The system boots and runs fine showing all 8K of installed memory (see photos). BASIC programs typed-in run properly: a simple program that writes directly to video RAM was run to test it (followed by the game loaded via the serial port as described above).
Some traces have been soldered (or rather re-soldered), some chips look like they have been replaced, and there are some extra holes apparent at the top of the board where the optional on-board power supply would go (it almost looks as if someone installed such a supply at one point), but it is a decent working machine especially for its fourty-one year age. Be prepared to give little TLC and perhaps the odd simple repair like cold solder joints of the keyswitches on the bottom of the board which seem to plague some of these machines leading to "flaky" keys.
Includes a coaxial cable to connect to a composite monitor. Power is supplied via two stripped wires. No other cables (e.g. for cassette) are supplied.
Needs a 5 Volt, 3 Amp regulated power supply to run as well as an NTSC composite monitor (or perhaps an old VCR which accepts composite input but not all work with a source like this). Please check your supply with a DMM before connecting to ensure the voltage is correct and stable.
Tested as above, but due to age it is sold "as is"
Shipping is by Canada Post tracked parcel. INTERNATIONAL BIDDERS (not continental USA, e.g. Europe) please contact first as Canada Post is not shipping to all countries due to CoVid and there will likely be large delays to some countries as well. Import taxes and duties are the responsibility of the purchaser.
Combining shipping: we are happy to combine shipping. If you win more than one item please contact us BEFORE paying and we will send an invoice for the combined items.
This single-board complete computer features built-in 24 line by 24 character video with NTSC composite output, Microsoft 8K BASIC in ROM, 8K of RAM (in the form of sixteen 2114 1K*4 chips). The standard installed monitor firmware allows access to machine code as well as boot to expansion floppy disk (if installed via an optional 610 expansion board). On-boar...d cassette interface (load/save) was not tested as this machine is currently configures to use RS-232 upload/download. Some traces on the board are cut and some have been re-soldered: like many computers of the day, some circuitry might well have been modified for a specific use (RAM expansion on the board, video modifications to 32 columns, or even overclocking to 2MHz). These machines were very popular with the hobbyist/experimenter crowd so many C1P's from this era have modifications of some type. Essential circuitry on this board has been restored to the original factory design. The Monitor and BASIC ROMs are Xicor 2816 2K EEPROMs (burned with firmware from the same revision board) while the character generator ROM is a factory masked 2316 type.
The video output (NTSC composite) comes via an RCA cable which mates with a connector on the board.
Testing was performed as follows:
Upon power-up (or when the reset key is pressed) the "D/C/W/M" prompt appears. Ensure the CAPS LOCK button is down and press "C" followed by ENTER several times to enter BASIC. The system shows 7423 bytes free (8K minus memory used by the system including page zero for the 6502, variables for basic, and the stack).
The keyboard was tested by pressing each key. A BASIC program was then entered via the keyboard and run (primarily to test the keyboard).
The ACIA was tested by typing SAVE then LIST at which point characters appear at the (slow) rate of about 120 per second on an external serial terminal: since the board has a built-in serial interface, the RS-232 Data Out signal on J3 (pin 2) was run to a PC running TeraTerm and characters on the screen were echoed to the terminal. No testing of the cassette port was done at all (since this would require reconfiguration of the machine ... see below ...). The connector on J3 is currently wired for serial RS-232 operation at 1200 baud but it can be wired for cassette operation (at 300 baud). Use of the serial port to upload/download programs is a more reliable method though.
The ACIA is currently configured for 1200, N, 8, 1 for transfers via the RS-232 port ... for use with the cassette port it will be necessary to reconfigure this (the cassette is hence untested). To test the machine, the on-board serial interface was wired to a PC as follows:
J3 pin 1 = Ground
J3 pin 2 = RS-232 Transmit to the PC
J3 pin 3 = RS-232 Receive from the PC
J3 pin 4 jumpered to J3 pin 6 (this is the RC Clock)
Running TeraTerm on the PC, once can transfer programs up to the OSI as follows: Set TeraTerm transmit delays for 20ms between characters and 500ms between lines (remember that this machine was designed for cassette storage at 300 baud), Type "LOAD" on the OSI, Send the BASIC program as an ASCII file from the PC to the OSI, when done type on the OSI and RUN the program. It was tested with Seawolfe by Rodger Olsen (Aardvark, 1978) - it loaded the program and ran it fine (this also allowed testing of the video memory).
The keys are raised in rows for use in a case: when I bought this unit many years ago it was in a home-built wooden case, and while I always intended to solder the keys back to their original positions flat on the board, raising the keys like this is exactly what is needed to when placing this board in a case so the keys fit the sloped front properly! The keys are mounted on a fiberglass piece with jumper wires connecting them to the main board underneath.
All keys were tested to work (see the photo of characters produced from keypresses) albeit some are a bit "sticky". The system boots and runs fine showing all 8K of installed memory (see photos). BASIC programs typed-in run properly: a simple program that writes directly to video RAM was run to test it (followed by the game loaded via the serial port as described above).
Some traces have been soldered (or rather re-soldered), some chips look like they have been replaced, and there are some extra holes apparent at the top of the board where the optional on-board power supply would go (it almost looks as if someone installed such a supply at one point), but it is a decent working machine especially for its fourty-one year age. Be prepared to give little TLC and perhaps the odd simple repair like cold solder joints of the keyswitches on the bottom of the board which seem to plague some of these machines leading to "flaky" keys.
Includes a coaxial cable to connect to a composite monitor. Power is supplied via two stripped wires. No other cables (e.g. for cassette) are supplied.
Needs a 5 Volt, 3 Amp regulated power supply to run as well as an NTSC composite monitor (or perhaps an old VCR which accepts composite input but not all work with a source like this). Please check your supply with a DMM before connecting to ensure the voltage is correct and stable.
Tested as above, but due to age it is sold "as is"
Shipping is by Canada Post tracked parcel. INTERNATIONAL BIDDERS (not continental USA, e.g. Europe) please contact first as Canada Post is not shipping to all countries due to CoVid and there will likely be large delays to some countries as well. Import taxes and duties are the responsibility of the purchaser.
Combining shipping: we are happy to combine shipping. If you win more than one item please contact us BEFORE paying and we will send an invoice for the combined items.
