DI Gerhard Kreuzer wrote: I have yet to be able to run it, but there is a simulation online at: http://page.mi.fu-berlin.de/zoppke/D/index.html Under 'Simulation' there are some documentation links including http://page.mi.fu-berlin.de/zoppke/D/doc/ENIACsim.pdf which gives a little more user-level detail of how the ENIAC functioned and was programmed (still not enough though). I'd still like to make up some web pages with a proper machine definition. One of the issues with making a sim is whether one wants to start from a machine definition and create your own logic, or do the logic as derived as closely as possible from the original schematic, although given the nature of the ENIAC that distinction probably isn't as great as it is for more typical processors.