HP-41 MCODE Wiki


Welcome to the HP-41 MCODE Wiki[]

This a collaborative effort to document the HP-41 calculator micro code (MCODE) programming. It was created by people over at the HP Forum interested in the HP-41 internals.

MCODE is the "under-the-hood" programming for the HP-41. It is the language of the calculator Operating System itself. With MCODE, you can add any functionality within the hardware capability of the little beauty. Programs written in MCODE can run 100 times faster than those written in FOCAL.

The purpose of this wiki is to collect MCODE tips & tricks, useful routines and relevant entry points for the OS - mainframe, HP-IL, printer, timer, etc. If you have something to contribute, find the right page below or create a new page, click "Edit" and add your information. If you create a new page, please remember to link to it from here or from one of the other pages below.

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