There is an error in the PDF version of the manual that bothered me, somewhat. In the bookmarks for Appendix B of the manual (the one dealing with DOS Function numbers), the function numbers don't correctly appear. Since the manual is editable, I modified my copy of it to place the correct numbers there. You may write me for a copy (until an IBM employee I can verify as authoritative tells me otherwise) if you would prefer mine over the one available at this site.

This web-based resource from Microsoft discusses some of the technical details of MS-DOS commands. For example, you can find a page that documents the commands for using DEBUG here. It's a great reference if you don't already have the MS-DOS tech ref book.

This site above is (or was) for a class and it may disappear. It appears that these PDF files were generated from the same Microsoft Word documents that went around the net for a while, as they are missing some of the same required images. But this would be an excellent off-line reference to get, in any case.

Intel makes available a number of manuals for their x86 processors. In the past, they maintained a number of slightly different version for each processor family. But now they have consolidated these into their IA-32 series, which includes information about a variety of processors. The first site mentioned above provides the links for these manuals. For those deeply into specific details of the processor, this link also provides a reference their "Specification Updates." The second site is for an older set of manuals, also still available from Intel, which may be useful.

Randy has an extremely generous web page on the subject of assembly language programming. It is without peer, frankly. If you are planning to do DOS programming, be sure to get a copy of his Art of Assembly version designed for 16-bit programming at DOS version of AoA.

Ralf Brown has maintained a terse and surprisingly complete "interrupt list" for IBM PC developers at his site. The above link takes you directly to the page where his list is currently maintained. You may also use "Ralf Brown's PO Box Link" to reach his site, if the above link is broken, as he keeps this link pointing to wherever his site is later moved. At this time, it's currently Release 61.

I mention this site mainly because Kip offers a free copy of Appendix C from his book -- on the CodeView debugger. Very glad to see it! Get the PDF file directly, here.

This is an important resource for anyone interested in digging more into assembly language with the x86 CPU. This site does move from time to time so the link may break, again. If so, you can check on comp.lang.asm.x86 newsgroup -- it is posted to this group once a month, I believe.

Ethan Winer has made his BASIC Techniques and Utilities book available on the web in PDF form, at no charge. It's a great resource for those trying to use Microsoft BASIC. Honestly! Get it.

I'm including several possible links here.