8. PROGRAMMING NOTES AND RESTRICTIONS

next, previous Section / Table of Contents / Index The BALSAC ((C) Copyright 1991-2005 K. Hermann) software package exists as a DOS PC and as a Unix workstation version. The PC version is developed to run on IBM PC/AT/XT, PS/2 or fully compatible personal computers using MS-DOS or PC-DOS 5.0 or later versions. The PC must be equipped with an Intel 8087 / 80287 / 80387 Math Coprocessor or an Intel 80487 / Pentium Processor. The BALSAC load module uses 560 kB of DOS memory. BALSAC can also be run as a full screen application inside MS Windows 3.x if the memory assigned to DOS exceeds 560 kB. Graphics require a CGA, EGA, or VGA graphics adapter. Compilation of the numerical parts was performed with the Microsoft (R) Fortran Compiler Version 5.1. Assembler graphics and interactive utilities were developed with the Microsoft (R) Macro Assembler Version 6.11. The workstation version is developed to run on Unix workstations and mainframes equipped with X.11 Windows (Release 3 or later) software. The workstation must include a color adapter and monitor allowing a minimum of 256 different colors. Compilation of the software requires a standard Fortran 77 compiler for the numerical part, an ANSI C compiler for the graphics interface, and the basic X.11 Windows library xlib. The system linker must be able to link Fortran and C objects together (language mixing feature). In the following internal parameter settings of BALSAC are always given as "Ndos/Nunix" to indicate different values of the DOS (Ndos) and Unix (Nunix) versions. Presently, BALSAC can handle clusters or crystal sections up to 2001 / 10001 (NKMAX) atom centers, 201 / 301 (NBGES) atoms per unit cell in crystals, 20 / 36 (NRLMX) restructured layers in crystal sections, 50 / 50 (NBRMX) inequivalent atoms in each restructured layer, 20 / 35 (NCNMX) constraints to connect atoms by lines/sticks, 40 / 55 (NALMX) additional lines in plots A listing of the internal parameter settings of BALSAC can be obtained with > balsac -h at the DOS or Unix command level yielding INTERNAL LIMITS: Atoms = NKMAX Atom basis in crystals = NBGES Layers restructured = NRLMX Atoms in restructured layer = NBRMX Atom link constraints = NCNMX Additional lines in plots = NALMX The size of meaningful lattice sections or clusters is restricted also by the resolution of the graphics adapter. A section of 35 x 35 atoms per lattice plane seems to be an upper limit (also depending on the view, view options, stereo mode etc.). If any of the above parameters exceeds its internal maximum a warning will be issued and the cluster or lattice section will be truncated accordingly resulting in incomplete structures. next, previous Section / Table of Contents / Index