On Thu, May 3, 2012 at 10:05 PM, Henry Lee <henry_...@fastmail.fm> wrote:
> I just went through the FreeDOS install howto and eventually got > everything to work, but I ran into an issue. One of the steps of the > howto says to edit autoexec.bat changing the line "REM LH PCNTPK > INT=0x60" to "LH PCNTPK INT=0x60". This didn't work for me. Somehow the > packet driver was never actually loaded on startup. What did work is > changing the line to "PCNTPK INT=0x60" without the LH. I'm not much on > batch scripting so I'm not totally sure what "LH" does, but some > googling reveals that it means Load Highmem. Can anybody give me an > explanation? LH is an abbreviation for LOADHIGH. The systems on which MS-DOS was first used had a one MB address space. Of that, 640KB was "conventional" memory, available to applications. The memory above 640K was reserved for the system and things like video memory. It was possible to load some things in unused space in the area between 640KB and 1MB, and this space was referred as "upper" or "high" memory. You made it available by loading the HIMEM.SYS driver first. There was a LOADHIGH command usable in AUTOEXEC.BAT, and a corresponding DEVICEHIGH command usable in CONFIG.SYS. The problem was how much high memory was available. Depending on what all you wanted to load high, there might not be room for everything. One of the things users learned to do was play with the order in which stuff loaded, because they would require more memory to install and initialize than they took once loaded. A program might fail to load high because there wasn't enough memory to hold it during the load and initialize phase if other stuff was already loaded, but *would* install if loaded earlier, with the other stuff loaded after it. Your issue looks like either HIMEM.SYS wasn't loaded, and no high memory was available, or there was insufficient room in upper memory to load PCNTPK. > Cheers, > Henry ______ Dennis https://plus.google.com/u/0/105128793974319004519 ------------------------------------------------------------------------------ Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ _______________________________________________ Freedos-user mailing list Freedos-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/freedos-user
