Subject: Re: "DOS from Drive A" fails with "Illegal Inst
Date: 12 Nov 1992 06:44:16 GMT
Organization: AWA Defence Industries
Lines: 28
Distribution: world
Message-ID: <1dsug0INNmjf@myall.awadi.com.au>
References: <1dpubcINNh9u@myall.awadi.com.au>
Reply-To: dhichens@awadi.com.au
NNTP-Posting-Host: sallee.awadi.com.au
Summary: Problem fixed!!
>
>G'Day,
>
> Has anybody come across the problem of "DOS from Drive A" failing with an "Illegal Instruction" error? The problem occured both before and after installing the service pack.
>
> Thanks for any assistance.
>
>
> Regards,
>
>
> David Hichens.
G'Day,
I contacted IBM support in Sydney and someone there came up with a fix. The problem was traced to the ROM BIOS on my machine being too slow. Thus, illegal instructions were being extracted and executed.
The solution was to set the `HW_ROM_TO_RAM' setting under `DOS settings' to on and reduce the `DOS_RMSIZE' setting to 624K to make room for the ROM mapping. The ROM BIOS settings were then accessed from (much faster) RAM which eliminated the problem. It was suggested that I do this for all DOS sessions even though I have not had this problem with normal DOS sessions.
In article 1dpubcINNh9u@myall.awadi.com.au, dhichens@awadi.com.au (David Hichens) writes: