aubrey@val.UUCP (Aubrey McIntosh) (04/03/89)
In article <11641@ut-emx.UUCP> kjm@ut-emx.UUCP (kjm) writes: >I just recently received a copy of Minix 1.2. I just tried to use it this >evening. So far, I am severely underwhelmed. > >I'm running on a semi-homebrew AT clone, based on the Jameco Baby AT board. >(It uses the Award BIOS; runs PHOENIX MS-DOS 3.3 OK.) I can boot Minix OK, >mount and unmount floppies OK, run programs on the floppies OK, but I have >two rather wierd problems: > >1) The cursor sometimes goes away when it is in the bottom half or so of > the screen. Doing 'clr', moving it to the top half or so of the screen > (in mined), or just continuing on will generally bring it back a little > bit later. This cycle repeats ad nauseam. > [ second problem -- hard disk -- deleted ]. >Kenneth J. Montgomery "Shredder-of-hapless-smurfs" >Charter Member, Heathen and Atheist SCUM Alliance, "Heathen" division > >kjm@hermes.chpc.utexas.edu University of Texas System >kjm@cerberus.chpc.utexas.edu Center for High Performance Computing Friday night I stayed and rebuild Minix 1.1 on the company's True AT with a Genius full page monitor. The screen disappearance problem occured on this monitor also. Some perusal of the book lead me into tty.c, and into the scrolling routines... It's a miracle it ran at all, since the Genius doesn't use a 6845. They implement everything in PALs. However, the cursor location, begin, end and video memory start information acts as if it were a 6845 at the standard monochrome address. There is an assumption in tty.c about how much memory is available for the video, and where the hardware will fold things. For the genius, I changed the lines_per_page to 66, and the M_VID_MASK value to 0x3FFF. On the path to that change, I used symdeb to fill video memory with address specific values, and then rebooted Minix. When I got to the screen disapearing section, I could then see what part of memory was being displayed. That helped clue me in about what my system was doing. This may have nothing at all to do with the EGA fix... Drop some e-mail, I'd like to know who is using Minix locally. -- Whatcha' call a boomerang that doesn't come back? --Lost-- -------------------------------------------------------------- 1-(512)-346-5781 (v) Using Modula-2. Austin, TX 78759 ...!cs.utexas.edu![dell|oakhill|kvue]!val!aubrey