Serial port Yost standard combines DSR and DCD. Some serial ports on motherboards or add-in cards provide jumpers that select whether pin 1 of the DE-9 connector connects to DCD or a power supply voltage, and whether pin 9 of the DE-9 connector connects to RI or a power supply voltage. The power supply voltage can be +5V, +12V, +9V, or ground. (Selection varies by vendor.) The power is intended for use by point-of-sale equipment. Makers include Dell, HP, and others (This is not an official standard.) Operating systems usually create symbolic names for the serial ports of a computer, rather than
Parallel universes in fiction or unintentionally – as in "Angel Heart". Less often, the alternative narratives are given equal weight in the story, making them truly alternative universes, such as in the German film "Run Lola Run", the short-lived British West End musical "Our House" and the British film "Sliding Doors". More recent films that have explicitly explored parallel universes are: the 2000 film "The Family Man", the 2001 cult movie "Donnie Darko", which deals with what it terms a "tangent universe" that erupts from our own universe; "Super Mario Bros." (1993) has the eponymous heroes cross over into a parallel universe ruled by