It doesn’t occur typically that we report on new vacuum tube primarily based laptop designs. At present nonetheless, we’re happy to introduce to you the Fast Reliable Electronic Digital Dot Computer, or Fred.Pc for brief. It’s the brainchild of [Mike] who additionally introduced us ENA, which we featured earlier.
Fred is a brand new design that reuses the components that made up ENA. It has an 8-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 complete provide present of about 200 A it additionally gives a good bit of heating to [Mike]’s research. The principle logic is applied via NOR gates, constructed from 6N3P dual-triode tubes sourced from Jap Europe. These NOR gates are mixed into extra advanced constructions like latches, registers and even an entire ALU. A complete of sixteen machine code directions can be utilized to write down packages; intelligent design permits Fred to carry out 16, 32 and even 64-bit calculations with its 8-bit ALU.
An attention-grabbing addition is a brand new RAM design primarily based on reed relays. [Mike] realised that relays are literally similar to digital transmission gates and may due to this fact be used to make a easy static RAM cell. For those who thought relays had been too sluggish for RAM cells, assume once more: these reed relays can toggle at a mind-boggling 700 Hz, making them greater than quick sufficient for Fred.
The principle I/O gadget is a console that incorporates a number of pushbuttons in addition to a 12 x 8 LED show. All of this makes Fred a fully-functional general-purpose laptop that’s even able to enjoying Pong (video, embedded beneath). [Mike]’s web site is stuffed with attention-grabbing element on all features of vacuum tube laptop design, and makes pleasant studying for anybody tempted by the concept of constructing their very own.
Can’t get sufficient of vacuum tube computer systems? Take a look at this 1-bit MC14500 implementation, marvel at this modern interpretation of an adding machine, or discover out how IBM designed its logic in the 1950s.