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Using Fortran Compilers with TRNSYS

TRNSYS is written in the Fortran programming language.  Originally written in Fortran 77, it can be compiled with either a Fortran 77 compiler or a Fortran 90 compiler.  If a Fortran 77-only compiler is used, some TRNSYS features cannot be used. The use of TRNSYS 15 with some common Fortran compilers is described in the next few pages.

Using TRNSYS with Microsoft Windows 95/98, Windows 2000 and Windows NT 4.0

For TRNSYS owners considering the purchase of a new Fortran compiler, the Compaq Visual Fortran 6.6B compiler is recommended. Effective April 1, 1997, Microsoft discontinued sale of its Fortran PowerStation 4.0 compiler and recommended DIGITAL Visual Fortran 5.0 as the approved upgrade product. At the beginning of 2000, Digital sold the compiler to Compaq who now maintains the program. The TRNSYS development team at the Solar Energy Lab and in Europe has evaluated the Compaq compiler and determined that it works with the current version of TRNSYS. Compaq's brochure for Visual Fortran states that it has a "high level of compatibility with the Microsoft Fortran PowerStation 4.0 compiler." However, some of the newer TRNSYS features that make use of the Windows Operating system are NOT supported by PowerStation 4.0. TRNSYS owners currently using the discontinued Microsoft Fortran PowerStation 4.0 compiler need not upgrade as long as they are willing to do without Type56 (multizone building), Type61 (calling external DLLs), Type66 (calling EES routines) and the callprogram feature. Compaq Visual Fortran 6.1 is available worldwide.

The Compaq Visual Fortran 6.6B, 6.6A, 6.6, 6.5A, 6.5, 6.1, Digital Visual Fortran 5.0 and 6.0 compilers can produce the necessary 32-bit Dynamic Link Library (trnlib.dll) of Fortran subroutines required by the TRNSYS executable (trnsys.exe).  All of them have powerful development environments with extensive debugging capabilities. All four compilers are for use only with Windows 95/98 Windows 2000 or Windows NT 4.0.

A few simple tips will help you get started using the Compaq Visual Fortran 6.6A, 6.6, 6.5A, 6.5, 6.1, Digital Visual Fortran 5.0 or 6.0 compilers to create, compile, debug, and link your own subroutines for use with TRNSYS 15. Check the pages below this level for more information. If you are using the Microsoft Fortran PowerStation 4.0 compiler, click on the link in the next section for instructions on removing the TRNSYS 15 features which are incompatible with older compilers.

Compiler Specific Instructions for Working with TRNSYS and Windows 9x/NT/2000

NOTE: If you are running CVF 6.5, 6.5A or 6.6, we strongly recommend you to upgrade to CVF6.6B. 
Please refer to the Compaq Visual Fortran website for further information. All necessary upgrades are free of charge. 

Using TRNSYS with Windows 3.x, DOS, UNIX, Linux, or Other Operating Systems

TRNSYS 15 can be re-formulated to work as a stand-alone program outside the Windows operating system.  In this way , the source code (included with any TRNSYS package) can be used on any platform that supports Fortran.  However, none of the utility programs available with the current TRNSYS package (such as TRNSHELL, TRNSED, the on-line display, PREBID, etc.) are available for platforms other than Windows 95/98 2000 and Windows NT 4.0. It is not recommended that TRNSYS be purchased for use on operating systems other than Windows.

Other Fortran Links

The Fortran Market

Fortran 90 Software Repository (Numerical Algorithms Group Ltd, Oxford UK)

Fortran FAQ

Interesting Places

Fortran Compiler Beckmarking

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