An HP-35 (could be) workaround for ln 2.02

[Thomas Klemm]

(07-10-2024 01:29 AM)Matt Agajanian Wrote:  if Cuvee’s app accurately clones a Version 1 35

From RPN-35 SD — The first photo-realistic HP-35 simulator for the iPhone:

Quote:RPN-35 SD is a photo-realistic simulation of Hewlett-Packard's break-through scientific hand-held calculator.

I doubt it does.

(07-10-2024 01:29 AM)Matt Agajanian Wrote:  Here it goes:

2.02 log
1 e^x log ÷

.7030975115 shows up

(07-10-2024 04:52 AM)teenix Wrote:  On my HP-35 red dot emulator, I get .7030975113 after the division

Using this microcode-level emulation of the HP-35 running the original v2 ROM I get the same result:
.7030975113

As mentioned in 4.2) The so called “idiosyncrasy”:

Quote:The HP35 errata sheet says “The idiosyncrasy is in the e^x function, not in the logarithmic function.”

Apparently the buggy implementation is very sensitive to this value.
In both cases of the ROM (v2 and v4) the LN function of 2.02 returns the same value .7030975114.

However, in case of the buggy ROM v2 using .7030975114 instead of .7030975113 returns 2. instead of 2.02.
This was fixed in ROM v4.