Andy Goth wrote: > "Andy Goth" <[EMAIL PROTECTED]> wrote: >> I'll test the current SVN this Friday, or perhaps Thursday night at >> the earliest. > > Actually I did spend time tonight investigating. I needed to get the latest > SVN for another reason (about which I have questions I'll ask in a few days), > so I went ahead and looked into my scrolling input problem. > > Yup, still there. Today's SVN is affected. > > The problem is present when actually booting using GRUB (ordinary VGA text > mode), but it all works fine in grub-emu. > > Wait, I take that back. In grub-emu, typing very long lines (that wrap and > *cause the screen to scroll*) results in the text wrapping at column 80 > instead of column 79, so that there is *not* a white space character in the > rightmost column. Pressing Ctrl-U from such a line will only erase only the > bottom line of text, except for the first six characters (which presumably > correspond to "grub> "). > > Something's flaky! However, this grub-emu stuff might be unrelated to the > problem I've been having with the actual boot loader. > > I also add that in grub-emu, the carriage doesn't return after printing an > error message, so I get a stairstep effect. With such an indented prompt, > issuing a command like "ls" causes output to be printed to the *left* of the > prompt. > > Enough about grub-emu. In the actual boot loader, I noticed that the pattern > seems to be: it will scroll the screen if inserting text will cause the last > character to overflow the right edge of the screen. That sounds like the way > it should be, right? The problem is that only currently visible characters > appear to be checked for overflow. This doesn't include the character being > typed or characters that previously have failed to scroll onscreen. > > Test cases: > > 1. Near the top of the screen, type a bunch of text and overflow the edge. > Works fine. > 2. Hold down enter until the screen starts scrolling. Works fine. > 3. Type a bunch of text and overflow the edge. Fails to scroll! > 4. Use the left arrow key one or two times and type text. Fails to scroll! > 5. Use the left arrow key until the cursor is onscreen, and type text. > Everything scrolls into view. > > I'd absolutely love to debug all this and provide patches, but I really don't > have time right now. In fact I didn't have time to do the research I did; I > should have been sleeping. :^(
This seems to be BIOS issue in a way. In startup.S grub_console_real_putchar there is quite good comment about what are BIOS limitations. Choices are to modify this code here, or make better bios console terminal. _______________________________________________ Grub-devel mailing list Grub-devel@gnu.org http://lists.gnu.org/mailman/listinfo/grub-devel
