Trig Tangent Bug (3884 version WP-34S)

[BarryMead]

In an effort to NARROW DOWN the cause of this bug, I did an SVN checkout of the 3883 version of the WP-34S repository (One version older than the latest 3884 version) to see if this bug was happening on that version. I compiled a realbuild for that 3883 version and flashed my real calculator with that firmware, and it DID NOT exhibit the bug. So the bug was definitely caused after Paul Dale added the improvements to the trig function accuracy in the 3884 revisions. There may not be any logic errors or programming mistakes in this revision, but at least we now know for certain that this is when the bug first occurred, so it should be helpful in investigating the issue, as we can concentrate on only the changes between the 3883 and 3884 revision. It could be that the changes made caused the stack usage to exceed available stack space. If there is anyone on the forum that still has a working hardware debugger it would be helpful to see the bug happen in real time so we can gain a better understanding of what is going wrong, and how to approach a solution. At the moment it is difficult to find the bug since it does not present in the emulator.
I hope this helps, Barry

If you want to know how to grab a copy of the 3883 SVN version, this is how I did it.

svn checkout svn://svn.code.sf.net/p/wp34s/code -r 3883 wp34s-3883

This command will create a fresh SVN download of the 3883 version of the SVN repository and put it into a directory named wp34s-3883.