Level Extreme platform
Subscription
Corporate profile
Products & Services
Support
Legal
Français
FoxPro 2.0 DOS and the Extended Version
Message
From
26/06/1999 20:25:32
 
 
To
26/06/1999 20:09:55
General information
Forum:
Visual FoxPro
Category:
Troubleshooting
Miscellaneous
Thread ID:
00234106
Message ID:
00234412
Views:
35
>Hi Paul --
>
>FoxPro 2.0 DOS extended is different than FoxPro 2.5 DOS extended. I need some type of memory manager to emulate expanded memory. If memory serves me correct, I don’t believe that 2.0 can use extended memory.
>
>That's correct ... 2.0 needed expanded memory. I don't know why EMM386 is not working for you, but I will say that I ran into some weird stuff with my 2.0 app on occasion and when that happened, just said screw it and let it run in standard instead of extended. Could be some weird hardware configuration or something. I could never explain why it didn't work when I had that problem, because most of the time it ran just fine.
>

There are a number of variants of EMS, and 2.0 got confused in some cases when it saw EMS available from EMM386 where it couldn't allocate a fixed 64K swap area in the UMBs to use for EMS paging (in theory, EMS should be able to use 4 non-contiguous 16K frames to provide the EMS swap space, but the early version of the Watcom DOS Extender used by 2.0 wasn't very forgiving in my experience.) I had far fewer problems with 2.0's extended version using QEMM or Helix's memory manager rather than HIMEM/EMM386, both of which could be easily configured to convert freely between XMS and EMS allocation on the fly, and would move things around in the UMBs to make a contigous 64K block if at all possible.

>BTW, I’m still using 2.0 because I need to convert this application to Y2k, and I don’t want to rock the boat in converting it to FoxPro DOS 2.5. There are some serial communications in this program that are currently working. So I’m going let sleeping dogs lie and use the standard version of FoxPro2.0 and tweak the upper memory area.
>
>My app is still in 2.0 for some of the same reasons as yours ... serial communications that are working just fine, and if it ain't broke, don't fix it < g >.
>
>Good luck,
>Bonnie
EMail: EdR@edrauh.com
"See, the sun is going down..."
"No, the horizon is moving up!"
- Firesign Theater


NT and Win2K FAQ .. cWashington WSH/ADSI/WMI site
MS WSH site ........... WSH FAQ Site
Wrox Press .............. Win32 Scripting Journal
eSolutions Services, LLC

The Surgeon General has determined that prolonged exposure to the Windows Script Host may be addictive to laboratory mice and codemonkeys
Previous
Next
Reply
Map
View

Click here to load this message in the networking platform