It doesn’t happen typically that we report on new vacuum tube based mostly personal computer types. Currently having said that, we’re delighted to introduce to you the Fast Reliable Digital Digital Dot Computer system, or Fred.Computer system for limited. It is the brainchild of [Mike] who also introduced us ENA, which we showcased before.
Fred is a new design that reuses the sections that created up ENA. It has an 8-little bit CPU, 16 bytes of RAM, 256 bytes of NVRAM, and runs at a clock velocity of 11.3 kHz. With its 560 tubes drawing a overall offer present-day of about 200 A it also provides a reasonable bit of heating to [Mike]’s analyze. The main logic is carried out by way of NOR gates, built from 6N3P twin-triode tubes sourced from Japanese Europe. These NOR gates are mixed into additional complex structures like latches, registers and even a finish ALU. A overall of sixteen machine code instructions can be used to write plans clever layout permits Fred to perform 16, 32 or even 64-little bit calculations with its 8-bit ALU.
An appealing addition is a new RAM design dependent on reed relays. [Mike] realised that relays are in fact very very similar to digital transmission gates and can for that reason be employed to make a simple static RAM mobile. If you thought relays were much too gradual for RAM cells, imagine yet again: these reed relays can toggle at a brain-boggling 700 Hz, making them more than rapidly plenty of for Fred.
The major I/O device is a console that contains a number of pushbuttons as well as a 12 x 8 LED exhibit. All of this helps make Fred a absolutely-purposeful typical-function computer that is even able of taking part in Pong (movie, embedded underneath). [Mike]’s web site is comprehensive of intriguing element on all aspects of vacuum tube personal computer design and style, and helps make pleasant reading through for any individual tempted by the thought of setting up their possess.
Just cannot get adequate of vacuum tube personal computers? Have a glance at this 1-bit MC14500 implementation, marvel at this modern-day interpretation of an incorporating machine, or obtain out how IBM intended its logic in the 1950s.