MP-A2 Microprocessor / System Board
The MP-A2 board is the primary logic board for the SWTPC 6800 Computer system. It is a 5 1/2 inch x 9 inch circuit board containing the 6800 microprocessor chip, the 6830 ROM which stores the Mini-Operating system and the 6810 128 byte scratch pad memory for the ROM. There is a crystal controlled baud rate generator providing serial interface baud rates of 110, 150, 300, 600 and 1200 baud. The board also contains a power up/manual reset circuit, which loads the ROM stored operating system when activated. Full I/O buffering is provided for the 16 address lines and 8 bi-directional data lines with these and other inter-connections made to the rest of the system thru a fifty-pin connector to the mother board (MP-B).
The new MP-A2 board superceded the MP-A board originally provided with the SWTPC 6800 Computer System and comes equipped with the following features:
Socket provisions for up to 8K of Intel 2716 pinout EPROM,
PROM or ROM
Relocatable EPROM/PROM addressing for custom monitor or dedicated controller applications.
SWTBUG or MIKBUG compatible-switch configurable
Introduced by Southwest Technical Products Corporation in early 1978 and the MP-A2 kit cost $145.
Board Photo High Resolution (271K JPG)
Assembly Instructions (115K PDF)
System Checkout (68K PDF)
Modifying the MP-A2 for 8K of RAM (170K PDF)
SWTBUG Users Guide (245K PDF)
Schematic (314K JPG)
MC6875 Data Sheet