41CL Module Dependencies

[Howard Owen]

I have an early v2 HP-41CL that shipped with a ca. 2011 flash. I'm preparing to update the flash following the procedure outlined at at systemede.com After transferring the YFNF 1D module onto the calculator and mapping the RAM image into port 1U, I get garbage on cat 2, right after "YFNS 2B" The calculator display flickers and the calculator locks up for a time. Pressing on/off, delete, (separately) program and alpha for a few seconds, unlocks the calculator without MEMORY LOST (Cursing does not seem to affect the final result.). There seem to be only three possibilities to explain this. Either the uploaded data is corrupt in some way, a bonehead user error has occurred, or the YFNF 1D module is in some way incompatible with some aspect of the old flash contents. I've verified that the uploaded data has the right values in 000 and FFB through FFE. I could go farther than that, but the experiment seems to work to a 1st approximation. The second possibility is always on the table, God knows, but if it is user error I keep making the same mistake over and over. (Yes, a definition of insanity etc. etc.) The third possibility seems plausible.

Here are the particulars if my setup:

Mac with El Capitan
Y.C. USB to serial with native drivers
"Serial" terminal 4800 baud, 8N1, binary upload
41-CL BAUD48

The transfer finishes on the computer and YIMP subsequently returns. The XROM number and .NAME values agree with the source. I think that piece is solid. I think I'm probably missing a dependency. Can anyone help?

Thanks

[Ángel Martin]

I may be wrong but I think YFNF expects the YLIB ROM plugged at address 0x00B. It may also need the Flash Database ROM (FLDB.ROM) loaded in flash, at address 0x0DE. Try adding that one and see if there's changes. Oh and while you're at it you can also update your IMDB.ROM with the latest revision, at address 0x0DF. Hope this helps.

[Monte Dalrymple]

YFNF is self-contained, without any dependencies that I am aware of. The fact that YFNF doesn't show up when you do a CAT 2 suggests that there is something wrong with the FAT in the downloaded copy. If you hit R/S to stop the CAT before it gets off into the weeds, and then hit ENTER to look at the individual function entries, it might point to where the problem lies. I would also double-check that CAT 2 works ok before you plug in YFNF.