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==COM Files==
===Introduction===
COM files are extremely simple
COM files were used by MS-DOS. They are raw binaries
MS-DOS creates and stores an info structure starting at offset 0 and ending just before 0x100, called the Program Segment Prefix (PSP). The PSP is made just before starting the COM program. More info about the PSP can be found [http://heim.ifi.uio.no/~stanisls/helppc/program_segment_prefix.html here]. PSP
COM files usually terminate with a RET instruction. The operating system starts the COM program using a CALL instruction, so RET returns to the OS, allowing any cleanup (like restarting the command prompt) to be handled by the OS.▼
▲COM files usually terminate with a RET instruction. The operating system starts the COM program using a CALL instruction, so RET returns to the OS, allowing any cleanup (like restarting the command prompt).
===Loading===
To load a COM file you need to load it to a low memory location,
==See also==
===Executables===
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