2066-pin processors

Am 05.01.19 um 17:01 schrieb John Larkin:

I still have an original HP35. That still should work if I could find a battery pack. The father of a class mate who worked for BB&C bought some for us because HP then had no consumer distributors.

Cheers, Gerhard

They work without the battery; the mains charger is sufficient.

You can get batteries here:

yes, but I have recycled the charger to charge a NiCd based ham radio rig. That involved changing that plastic plug to a LEMO connector. The original cable is probably still around but it's not worth searching.

I have this hp-41 app in my Android phone and Warren Furlow's virtual HP-41 in my windows virtual machines.

Wow. A virtual HP-41 running in a virtual Windows7 machine running under Linux Mint / VMware.

There is also a real HP-41 somewhere.

Cheers, Gerhard

That .... isn't the choice I would have made!

My desktop calculator is an "HP15" doing something similar.

Always hated half-RPN calculators, and calculators that give the wrong answer to 1+2*3.

Besides the RPN "gather everything together and then do operation" always suited my mentality better than the semi-algebraic "get half, specify operation, get the rest of what's necessary, do operation".

I have clips somewhere around here that hold three AA NiCd batteries together to fit the HP35/45s. My HP45 has a bad power switch but otherwise it works (at least the last time I tried it).

I have had PC Lint since forever and once had to use a specific early development C++ IDE compiler that tended to crash horribly if there were any syntax errors at all in the code it was being asked to compile.

I am a fan of McCabes CCI as a measure of code network complexity with the addition of a count of decision points so that a switch case gets a more favourable rating than a cascade of nested if statements.

CCI doesn't tell you where the errors are but if code has a high network complexity then it is a fair bet that it hides some latent errors. It is very handy for working out the minimum test vector set to span all code paths. It is always the seldom travelled paths that fail when used.

The Modula 2 compiler I use has dataflow analysis and by default (because the developers have a weird sense of humour) it will compile any references to uninitialised variables to a hard runtime trap. That is if there is any path to that variable whereby it isn't initialised it will fail on first use. It tends to annoy people who don't RTFM. It can be configured to issue serious warnings for all used before initialised, memory leaks and multiple set of a semaphore (or multiple frees) etc.

Where this sort of thing really scores is in the seldom used paths that are supposed to handle rare fault events but don't always get adequately tested in real life. It comes from a different lab but is similar to Coverity in its approach to finding bugs by parsing the language and checking that all paths lead to Rome. M2 has a rather more tightly defined language spec than C or C++ so it is easier than for C/C++. It is also more of a minority interest so less effort went into it.

A nice review of Coverity is online at ACM here:

I particularly like what it has to say about MS Visual C++.NET 2003 under the "Laws of Bug Fixing" "social vs technical".

There are quite a few now. They will usually let you try before you buy and/or send a tech sales guy to run the tool against a codebase demo. It is unusual not to be able to find some hidden serious bugs in a big project although people are not always best pleased to be shown this.

I think there is even a half decent one in the MS Enterprise edition for which they charge an arm and a leg. They have finally after much badgering included a cut down version in the free and student editions (basically if you don't get students into doing things right and doing the right things you are on a hiding to nothing).

Never used this one but it shows up as promising for C users.

Runtime wise I like Boundschecker for Windows stuff (since I am usually modifying other peoples code of sometimes dubious quality).

What does Coverity cost per seat?

Cheers

Phil Hobbs