Re: But why? Message #11 Posted by Andrés C. Rodríguez (Argentina) on 2 Sept 2002, 7:54 a.m., in response to message #10 by Juergen Rodenkirchen (GER)
Flags between 0 and 10 are controlled only by the user, and have no meaning for the system.
Flags between 11 and 29 are controlled by the user with SF or CF and also by specific functions like [USER], [ALPHA]; and have meaning for the system such as selecting radix and digits grouping, enabling or disabling the beeper, error handling, writing private cards, , overwriting write protected cards, controlling printer modes, enabling Autorun (we could call it AUTOEXEC nowadays), etc.
Flags 30 to 55 are system flags, the user cannot set or clear them except by specific functions like FIX, SCI, ENG, DEG, RAD, GRAD, ON; and some combinations are not enabled or not documented. The user can test them with FS?, FC?; but in some cases the results will be meaningless.
Synthetic programming, and the Extended Functions STOFLAG, RCLFLAG and X<>F instructions allow for advanced flag manipulation; these are the usual ways to test "invalid" flags combinations. I did some experimenting some years ago, without any remarkable result.
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