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
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
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