YFNX does not work on my 41CL

[Monte Dalrymple]

(09-18-2019 05:57 PM)hth Wrote:  OK, I tried to update the 008 sector. I downloaded the Update module to the MLDL, set up the 008 sector in RAM, picked new YFNX and YLIB over HP-IL and went ahead with P8UPD.

Pressing R/S and it indicates that it starts erasing sectors 008 and hangs there for a while. Eventually the display goes blank and if I try to get in control pressing keys the display comes on with characters that I have never seen before, like it is only showing the upper half of the segments for a weird low characters random view. I thought the HP-41 had a character set for the LCD and could not display characters like this, LOL.

I tried it twice with the same result (different but similar weird displays).

Anyway, I cannot seem to get it to work, any idea what is up?

The erase probably succeeded. Unless you've removed the batteries the sector image should still be good in RAM. YUPS may not like being run out of the MLDL. To be safe, copy YUPS to a page in RAM and then PLUG in that page. Power off and remove the MLDL. Run PGCRC on each page in the sector buffer and compare with the values shown in mem_ref.pdf to make sure that the images there are good. Then run P8UPD on sector 008. If you want to verify that the images are correct in Flash, run PGCRC on the updated pages. Then you should be good to go. Make sure that your batteries are not weak. The functions check the battery level before starting, but not during the operations themselves.