I dont know how to write it myself, but the original kernel scrolling code is in C. Might try OSDev forums. Not that I know of.
On 11/27/2013 09:24 PM, Serge Hallyn wrote: > Thanks for reporting this bug. Is there any other reproducer you can > give us? > > ** No longer affects: kvm (Ubuntu) > > ** Also affects: qemu (Ubuntu) > Importance: Undecided > Status: New > > ** Changed in: qemu (Ubuntu) > Status: New => Incomplete > > ** Changed in: qemu > Status: New => Incomplete > -- You received this bug notification because you are a member of qemu- devel-ml, which is subscribed to QEMU. https://bugs.launchpad.net/bugs/1239008 Title: qemu fails to scroll screen on ^Vidmem output Status in QEMU: Incomplete Status in “qemu” package in Ubuntu: Incomplete Bug description: Pascal uses ^Vidmem for B800 console output. The terminal does not oblige the Pascal OS code to scroll the output. Virtualbox emulation works, so this must be a qemu bug. Using QEMU in KVM mode as Ubuntu LTS. Source line to trip bug(in theory pushes VideoMem up one line): procedure Scroll; //this is whats causing crashes. FIXME:Virtualbox not affected.QEMU BUG? begin if scrolldisabled then exit; if (CursorPosY >= 24) then begin //in case called before end of screen blank:= $20 or (TextAttr shl 8); Move((VidMem+(2*80))^,VidMem^,24*(2*80)); // Empty last line FillWord((VidMem+(24*2*80))^,80,Blank); CursorPosX:=1; CursorPosY:=23; update_cursor; end; end; To manage notifications about this bug go to: https://bugs.launchpad.net/qemu/+bug/1239008/+subscriptions
