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PR#6

no, really, you old Apple users know what I mean. That's what you would type to get the thing to load DOS.

PR#3 got you into 80 column mode. I thought the PR# was to activate a card in a slot number.. but I'm not sure.

https://archive.org/details/iie-80-column-text-card/page/n29...

Apple2 Manuals where quite excellent back in the day. The internet archive has a bunch. Search friendly machine names the are not (Apple ii , apple//e, apple][ , apple //c.....)

In Unix terms PR# redirects the standard output to the hardware in the indicated slot and IN# redirects the standard input. From then on the BASIC commands PRINT and INPUT will access that hardware instead of the screen and keyboard respectively.

In practice the hardware can actually do anything it wants when you PR#, like booting from an attached floppy.

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