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AN HC11 FILE MANAGER

Part 2ýAll of the Details
by Walter Krawec

Introduction ý Format() ý Install() ý Directory() ý Run() ý Menu() ý Saving Memory ý Interfacing to the File Manager ý Two Sample Programs ý Conclusion ý Sources and PDF

Last month, I introduced you to the WCC11 compiler for the 68HC11 and how to code a simple program using it. This month, Iýll build the full file manager and show you how you can use it to manage the development of projects on the processor and share procedures among the projects.

The file manager is built using four source files (download all code for this article). FileMngr.c contains all of the procedures specific to the file manager. Itoa.c contains procedures for printing integers. Msg.c contains the strings of various messages that the file manager prints. And, SCI.c contains the support procedures for the 68HC11's SCI port. [1]

The file manager keeps a table of information that describes the installed programs in memory (see Figure 1). A variable in low memory, called prg_addr, points to this structure, and all accesses to it are relative to this pointer.

Figure 1ýThe file manager maintains name and position information for the installed programs.

I'll be referring to these files and this data structure as I go through the descriptions of the procedures that implement the file manager.

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