+Larry Posted November 10, 2007 Share Posted November 10, 2007 Is there an easy way to find the "footprint" (memory usage) of various DOS.SYS modules? I know that virtually all of them load at $700, but finding their end is causing me trouble. Thanks, Larry Quote Link to comment Share on other sites More sharing options...
Rybags Posted November 10, 2007 Share Posted November 10, 2007 MEMLO (dec. 743, 744) contains the lowest free RAM address pointer. So, once DOS loads, either use a monitor to view those locations - or you can just ?PEEK from BASIC. The end point of the load won't necessarily be the start of free RAM since DOS needs extra memory for workspace, buffers etc. Quote Link to comment Share on other sites More sharing options...
+Larry Posted November 10, 2007 Author Share Posted November 10, 2007 Thanks, Rybags! That is most helpful. MEMLO (dec. 743, 744) contains the lowest free RAM address pointer. So, once DOS loads, either use a monitor to view those locations - or you can just ?PEEK from BASIC. The end point of the load won't necessarily be the start of free RAM since DOS needs extra memory for workspace, buffers etc. Quote Link to comment Share on other sites More sharing options...
walter_J64bit Posted November 13, 2007 Share Posted November 13, 2007 MEMLO (dec. 743, 744) contains the lowest free RAM address pointer. So, once DOS loads, either use a monitor to view those locations - or you can just ?PEEK from BASIC. The end point of the load won't necessarily be the start of free RAM since DOS needs extra memory for workspace, buffers etc. Is this Atari DOS 2.5? Quote Link to comment Share on other sites More sharing options...
Rybags Posted November 13, 2007 Share Posted November 13, 2007 Any DOS. BASIC, or whatever language/app is used will use MEMLO as it's starting point to store programs/data. Quote Link to comment Share on other sites More sharing options...
+Larry Posted November 13, 2007 Author Share Posted November 13, 2007 Any DOS. BASIC, or whatever language/app is used will use MEMLO as it's starting point to store programs/data. Here are some MEMLO values for several Dos versions I have looked at thus far: Dos 2.0s $1CFC Dos 2.5 $1E1C MyDos 4.50 $1EE9 MyDos 3.07 $1BE9 OSS Dos from Basic XL toolkit $1B00 (this Dos can't load a DUP.SYS) Sparta Dos 3.2G $17A2 Sparta Dos X 4.22 $10FF (!!!) -Larry Quote Link to comment Share on other sites More sharing options...
drac030 Posted November 13, 2007 Share Posted November 13, 2007 (edited) Sparta Dos X 4.22 $10FF (!!!) Oh, this is quite high for this DOS. When properly configured, it can go below $0F00 PS. I can add something to your list: DOS 1.0 $2A80 Now, that's a "!!!" Edited November 13, 2007 by drac030 Quote Link to comment Share on other sites More sharing options...
walter_J64bit Posted November 15, 2007 Share Posted November 15, 2007 Hmmm, I see is there any way to show how much RAM is freed up by using the MEMLO? Quote Link to comment Share on other sites More sharing options...
Heaven/TQA Posted November 15, 2007 Share Posted November 15, 2007 Walter...? in Basic print free(0)? Quote Link to comment Share on other sites More sharing options...
Rybags Posted November 15, 2007 Share Posted November 15, 2007 DOS 1.0 always loaded DUP as well (from memory - I don't think I ever had the "pleasure") FRE(0) is just APPMHI - MEMLO APPMHI (14,15 dec) tells the OS the highest location that the application is using (ie BASIC or whatever language should set it as the program/variable storage grows) A neat trick on OSA and OSB (400/800) was to set APPMHI to something like $9D00 - the OS then would not be able to open a screen after System Reset, so it in a way was a means to protect software from funny business. The bug was fixed in the XL OS. Quote Link to comment Share on other sites More sharing options...
walter_J64bit Posted November 16, 2007 Share Posted November 16, 2007 Walter...? in Basic print free(0)? All I get is an error 9 Quote Link to comment Share on other sites More sharing options...
miker Posted November 16, 2007 Share Posted November 16, 2007 Not ?FREE(0) but ?FRE(0), tebe has something misspelled. Quote Link to comment Share on other sites More sharing options...
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