How to create custom 41C modules from keystroke programs?

[Didier Lachieze]

Another option using DOS tools from the HP-41 era available on the TOS DVD would be to use a User Code Compiler to create .BIN files from your user code programs (HHP 41UCC or Leo Duran's HP41UC) and then create a ROM with SDS II:

To create a ROM file:
Run 41P on UCC -> .BIN
Run READ41P (SDS II) on .BIN -> .41T
Use BUILD (SDS II) to create ROM file

EDIT: you can find an example of this method of creating a ROM from FOCAL programs here. With SDS II you can make your FOCAL programs private, define how XEQ are handled and specify key assignments.