The SWTPC 6800 Computer System is designed around Motorola’s outstanding 6800 microprocessor chip and its integral family of support devices. The basic system includes the following: 15 1/8” W x 7” H x 15 1/4” D chassis with cover, mother board, memory card with 2048 bytes of 8 bit static RAM memory, serial 20 Ma. TTY teletype­writer/RS-232 terminal interface card, micro­processor card featuring a ROM stored mini­operating system, power supply capable of driving the system with a full 16K bytes of memory, assembly instructions, diagnostics and programming manuals.  

The 6800 microprocessor chip used in the system is a full specification Motorola com­ponent featuring 8 bit parallel data process­ing, 16 bit — 65K address buss, 72 instruc­tions with seven addressing modes, maskable and non-maskable interrupts, two accumulators, an index register, variable length stack, DMA Capability, 1.1 microsecond cycle time and TTL compatibility.

The Motorola mini-operating system ROM used in the system gives the user complete teletypewriter/terminal control the instant the system is turned on. The ROM used is a standard Motorola part and makes the system program compatible with other Motorola products. The mini-operating system features a tape load/dump routine, a memory and register examine and/or change function and an execute user’s program command. 

In addition to the step-by-step assembly instructions included with the kit, there is a documentation package including Motorola’s M6800 Programming Manual plus our own 200 page loose-leaf notebook containing pro­gramming information and examples, diag­nostic and game programs and an application form to join Motorola’s M6800 User’s Group. 

The system has been designed using flexible plug-together construction on solder coated, doubled-sided plated thru hole circuit boards. The system boards are fully buffered with on board voltage regulators for minimum noise and maximum reliability. The processor is fed from a crystal controlled clock which simultaneously generates five independent baud rate clocks for selectable serial inter­face data rates. Any combination of up to seven optional serial or parallel interface boards may be plugged onto the system to interface the computer with external devices. These inexpensive interface options are also built around Motorola 6800 family chips and are actually programmable within themselves. 

Because of limited space, many of the SWTPC 6800 features and options could not be mentioned here. For complete information please write us and ask for document MP-01.

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