How to create custom 41C modules from keystroke programs?

[rprosperi]

It depends on what you want to do with the module. If you simply want to use those programs, then just install HEPAX and store your FOCAL programs in the 4/8/12/16k of HRAM. You don't need to know anything technical, it's as simple to use as extended memory, except programs stored in HRAM are always 'online' in the sense that you can just run them.

If you have the FOCAL program "FOO" in normal program RAM:

"FOO" [XEQ] HSAVEP to save the program into HRAM
[XEQ] "CLP" "FOO" to erase FOO from normal RAM

Then you simply do

[XEQ] "FOO" and it runs normally

And the upper RAM allocated to and managed by the HEPAX 4H module, can be saved to FAT and later loaded again.