Thread: hp-41cx / NoV-64d / Hepax XF multi-function

[kj.vandelooij]

Hello everyone,

I have a question about Hepax multifunctions on a HP-41cx with a NoV-64d module. When I key in a little program like

LBL TST
XF
0

and exit the program mode to run it, the result is 'nonextistent'. After this, entering program mode again shows

LBL TST
XROM 07,53
0

Only after turning the calculator OFF and ON again, with

H:FAT FULL

appearing in the display, the program is changed back into

LBL TST
XF
0

and executes fine, returning the length of the string in the alpha-register in the x-register

Note: there are no additional modules or hardware plugged in. Neither have I added any modules to the NoV-64d. I cleared all four RAM chips manually as per the procedure described in the NoV-64d manual.

Questions: 'Is this behavior normal? Is there a way around it? And if there is: How can I change things back to normal?'

Thanks for reading,

Kees Jan