HP-IL and EMU71

[Christoph Giesselink]

Hi together,

just updated my Virtual HP-IL example page from 2015.

The graphic is still from 2015, but now the "Setup the loop" picture contain arrows and a small description about the dependencies between "In Port" and "Out Port" to create a virtual loop.

There is still a document from the Allschwil Meeting 2014 with a short view behind the curtain Virtual HP-IL Concept.

Bob Prosperi made a presentation for the HHC 2014 meeting with the title Virtual Loops, PILS and LIF; An Update on HP-IL.

There's also a video of this presentation. The part how to configure a loop is around minute 35:00. But IMHO it's worth to view the complete video.

Over the years many tips and tutorials how to setup Virtual HP-IL have been published in this forum. So I will not give any individual support how to configure a loop configuration.

An essential is to understand the concept of real HP-IL with the HP-IL specific commands inside the calculator to control the loop. Therefore you have read the calculator manual and maybe extra literature about HP-IL.

Then you have to invest time to understand the concept of Virtual HP-IL. When you understood the concept behind you need no "try and error" any more to build a mixed HP-IL loop with real and virtual devices.

All my Virtual HP-IL device implementations and the HP41 emulator program V41 are written in C++. To run them you must install a compiler specific runtime. To be compatible with most Windows versions, the programs have been compiled with Visual Studio 2005 as x86 application and so you need the VS2005 runtime for x86: vcredist2005_x86.exe

But there's another important topic, Microsoft called it, the "DLL Hell". DLL's are made to have one implementation for a function which can be used by all applications on the Windows system. But the nature of code is, that it might be buggy or must be extended to integrate new features. The result is an equal DLL with the same name and with a new version number. But it sometimes happen, that a function inside the new DLL version behaves a little bit different and so it's incompatible with the prior version. To make it short, to get out of this hell, Microsoft introduced so called side-by-side DLLs. Side-by-side DLL's are the same DLL but in different versions. So each application can load the side-by-side DLL version the application was made with. If the application can't find the DLL version the program was made with, it accepts also a newer version of the DLL, but not an older version!

Back to my Visual Studio 2005 compiler installation. This installation also integrated the last available hotfixes and so the created application code need the latest VS2005 runtime with the highest version numbers. This vcredist2005_x86.exe file is not easy to find for download because older versions may have the same name but not working with the application.