This motherboard was manufactured by Quality Research Company of Spokane Washington in the early 1980s. The board is same size as a SWTPC motherboard and will fit in a standard SWTPC chassis.
The I/O address range is fully decoded and set to the standard 6800 space starting at $8000. By installing optional switches the I/O range can be moved to $E000 (for the 6809) or any other location. The I/O space is set to 4 address per slot.
Photo Top (JPG 92k)
Photo Top high resolution (JPG 1349k)
Photo Bottom (JPG 106k)
Photo Bottom high resolution (JPG 1911k)
Decoder Schematic (JPG 82k)
Buffer Schematic (JPG 75k)