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HP Forum Archive 19

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HP41 bugs - testing
Message #1 Posted by John Robinson on 3 Mar 2010, 7:08 p.m.

Hi All, are there comprehensive test steps written down somewhere to determine which bugs a 41c has ? If so, can someone point me to those please ?

Thanks John

      
Re: HP41 bugs - testing
Message #2 Posted by Namir on 3 Mar 2010, 7:23 p.m.,
in response to message #1 by John Robinson

You should have been there (when the HP-41C was launched in 1979)!!

      
Re: HP41 bugs - testing
Message #3 Posted by Allen on 3 Mar 2010, 8:12 p.m.,
in response to message #1 by John Robinson

A full list is in "Extend Your HP-41" available on the DVD Version 7

Main versions: 

ROM   Date codes   Comments
DDE   1926-1940
FDE   1936-1952
FEE   1951-2034
GFF   2035-84??
HFF   84??-Present CV version
NFL   2329- Present current CX version
      
Re: HP41 bugs - testing
Message #4 Posted by PeterP on 3 Mar 2010, 8:19 p.m.,
in response to message #1 by John Robinson

John, if you scroll to to the bottom here you see the range of serial numbers which have specific bugs.

A simple test to see if you have most/all bugs is the following: 49, Sto 00, SF IND 00

If the Bat-indicator goes on you have bug 3 and hence most likely all other bugs as well.

Cheers

Peter

Edited: 3 Mar 2010, 11:48 p.m. after one or more responses were posted

            
Re: HP41 bugs - testing
Message #5 Posted by Gene Wright on 3 Mar 2010, 10:01 p.m.,
in response to message #4 by PeterP

For bug 1:

48 SIGMA+ LASTX ... if 48 is not displayed, it has bug 1.

For bug 2:

999 ENTER 3 STO IND Y.... if this works, it has bug 2.

For bug 3:

49 STO 00 SF IND 00...if the BAT indicator turns on, it has bug 3. Note: this is 49, not 59.

BUG 4 is bad results from SIN for small angles. Can't remember the arguments.

The information below is from http://www.finseth.com/hpdata/hp41c.php 


#4: Early models compute the SIN of small angles incorrectly.

#5: CLP would only clear 1089 program lines.

#6: -67A/-97A prorams that contain combinations of number entry, EEX, and CHS do not translate correctly.  Example:

	EEX	CHS	7	CHS	5

translates to

	E-7-5

instead of

	1E-7	-5

#7: The second nybble of the seventh byte of Alpha is copies along
with the first six bytes during an ASTO.

#8: Early machines do not decompile programs if they are turned off
during PRGM mode.

#9: Executing CAT 1 while in PRGM mode, then interrupting it with R/S causes step labelling oddities.

#10: If flag 25 is set and MEAN or SDEV causes an overflow, some flags can be altered.

#11 (CW1): If a program at the end of CAT 1 is replaced or deleted, a return to that program will return into the new program or off-program memory.

#12: On early models, the function LN(1+X) gives wrong answers for
values of X between -.9990234374 and -1.00.

#13: On early models, the operation (.1)^-43 gives an answer of
9.999999999E42 instead of 1E43.
                  
Re: HP41 bugs - testing
Message #6 Posted by Namir on 4 Mar 2010, 7:27 a.m.,
in response to message #5 by Gene Wright

Gene,

And to know we paid sooo much for such faulty machines. I feel cheated by HP. <wink>

Namir

                        
Re: HP41 bugs - testing
Message #7 Posted by John Robinson on 4 Mar 2010, 7:19 p.m.,
in response to message #6 by Namir

Thanks All,

I have a 1954 serial number, with the "tall keys".

Cheers, John

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