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Does anyone know whether you can show the full 10 digit mantissa in the 41 series? I do not find this ability descibed in the owner's handbook and programming guide. In other words, when you have a big exponent number, some way to toggle viewing the mantissa, as you can on the voyagers and pioneers.



A full mantissa option does not exist by itself, but you can choose the largest FIX which is [GOLD KEY] FIX 9

You'll get 9 figures after the comma.


thanks! So, this means that any really large or small numbers will only display 8 digits in the MAntissa, because of the Exponent display tasking up space.



You could type up the PPC ROM routine for "MT" (ManTissa), which you can run to show the entire mantissa regardless of display setting.

Anyone have the listing handy for Bill?

Fix 9 does not display all digits in the mantissa if the number is too small or too large to be displayed in fix format. However, recall the X register to the alpha register and view the alpha register you can see all 10 digit mantissa and the 2 digit exponent.

Gene, Bill:

All 13 lines of the MT routine are listed on page 339 of the PPC ROM manual, which is included in the MoHPC CDs/DVD:

29 LBL "MT"
30 CLA
31 STO M
33 INT
34 X!=0?
35 (Append x'00')
36 X=0?
37 (Append x'A0')
38 CLX
39 ST+ M
40 X<> M
41 RTN

Note: The line numbers begin with 29 because of the way routines are stored in the PPC ROM. They don't matter. Also, you may want to replace the RTN with an END.

Typing this routine requires using either a Byte Grabber in order to make it possible to type up the synthetic lines. The MoHPC page for the HP-41 contains a link to a page that describes how to create the Byte Grabber key assignment.

Finally, if you don't want to mess with synthetics AND you can spare the contents of both the T and LASTx registers, you can simply perform a multiplication or division by a suitable power of 10, which will eliminate the pesky exponent from the display. Example:

Supposing the HP-41 shows "1.2345678E-12", you simply multiply the result by 1E12 (EEX 12 x).


Edited: 23 July 2003, 12:07 p.m.

Gene, Ernie, Chan Tran, Thibaut,

Thanks a lot for your help---this forum is FUN!

Now you've got me curious about nibbles and synthetic programming......uh-oh, I'm getting sucked in......

Best regards,


Now you've got me curious about nibbles and synthetic programming......uh-oh, I'm getting sucked in......

Too late to run away. You've just been infected with the SP virus! 8^)