LOGICAL SYSTEMS PRODUCT GUIDE:

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     "Programmer's Technical Reference for MSDOS and the IBM PC"
                              DOSREF (tm)
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 This is a disk-based programming reference. Not just a list of
interrupts, it is a for-real programmer's guide, packed with the
details real programmers need.  DOSref can go along with you
from machine to machine without the need for hauling reference
books around. It's great for consultants or travelling programmers.

 topics: BIOS and DOS interrupts and subfunctions (2.0 - 6.1)
         low memory and BIOS Data Area addresses
         EMS 3.2, LIM 4.0+, EEMS 3.2, VCPI 1.0+
         Microsoft Extended Memory Standard (XMS)
         Intel Communicating Application Standard (CAS)
         CD-ROM interface
         PC-DOS, Digital Research DOS, and several DOS environments
         DOS disk and file structure
         DOS device drivers, memory blocks, and control areas
         mouse programming - PC Mouse, Microsoft, Logitech
         most known "undocumented" interrupts and functions

 tables: hard disk setup and configuration parameters,
         ASCII and EBCDIC codes, keyboard scancodes and more

 DOSref contains well over three megabytes of text and source
code - the equivalent of half a dozen normal programming books. It
will save you money compared to printed books.

 Pricing: two HD diskettes and single-user license
 $24.95 (US funds) + $1.75 S&H