|MadSci Network: Computer Science|
Hi Fatemeh, I assume you are writing a program for a computer using a Microsoft DOS operating system. If not, you will need to ask your question again, and specify the processor and operating system. The Program Segment Prefix, or PSP, isn't really an assembly language instruction, it's a header built by DOS when your program runs. It occupies the first 256 bytes of memory, and contains information like the amount of available memory, where the available memory starts, the command line arguments, and so forth. You can find one description at http://iserver.ivc.cc.ca.us/faculty/dehrlich/ASMGUIDE/ ng6911b.htm. There is a lot of information available online, including numerous tutorials written at various levels. You'll get over 7000 hits with a search for "psp assembly language" on Google (www.google.com). A little searching there should turn up all of the additional information you need. Mike Westerfield Byte Works, Inc.
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