2  Requirements relating to the personal computer


2.1 Hardware


The program package LIAN requires an IBM-compatible personal computer. Basically an 80x86 / 20 MHz with arithmetic processor is sufficient, but: the faster the better, because the performance of the receive routines depends on the processor performance.


Your computer should have at least 4 MB extension memory. In terms of memory, the same is true as for the CPU: the more the faster.

Hard disk

The LIAN program files take up about 12 MB on the hard disk. The archive file created at runtime can occupy another 32 MB. Further files such as protocol file, TRP file and the back scroll buffer for online analysis need spare, too. It is therefore advisable to have about 60 MB space on the hard disk for LIAN.


The computer must be equipped with two serial interface ports (COM1 and COM2) and a 16-bit AT bus slot for fitting the expansion module. The dongle supplied must be fitted to the parallel interface LPT1 (printer interface) on the PC.


The supplied expansion module has to be installed for an optimal use of the program SIMO. It puts the two necessary interfaces COM3 and COM4 at the disposal. Please note, that the card requires the interrupts 10 and 11. These interrupts may not be used for any other purpose. The installation of the expansion card is not absolutely necessary.

Caution with motherboards with PCI Bus :

With these main boards, normally the BIOS assigns interrupts for the occupied PCI slots freely. Therefore you must mark the interrupts 10 and 11 used as ISA resources in the Bios PCI configuration.


Only printers connected to the first parallel interface ( LPT1 ) are supported. Your printer must be equipped with 8 bit character sets ( PC-8/ PC-850 ). These character sets include line characters as well as the ASCII characters.

2.2 Software

Operating system

As operating system, MS-DOS Version 5.0 or higher is required. Alternatively it is possible to use the operating systems Windows 95, Windows 98 or Windows 98se.

System configuration

Before starting the installation, you should check whether your PC is configured correctly :

The software package LIAN needs at least 1 MByte main memory.

The file CONFIG.SYS therefore must contain the following lines :


In order to guarantee a trouble free printer output it is necessary to supplement the AUTOEXEC.BAT as follows :


The program SIMO.EXE requires at least 600 Kbytes of the normal DOS main memory if it is to operate smoothly, and it also needs enough extension memory. By calling the DOS command MEM.EXE ( mem /p ), you can see how much main memory is available in your system. If necessary, you can organize the memory optimally by means of the program MEMMAKER.EXE. ( apply with caution and not under WIN 95/ 98 ) Also make sure that any TSR programs and drivers loaded leave sufficient high memory space free.

The disk cache SMARTDRV.EXE, for example, tends to occupy all available memory if no limits are set by means of parameters.

Is the driver SHARE.EXE loaded, conflicts can occur with the programs SIMO and TDEP. When you cannot do without this driver, you must enter 'i' to ignore, if there a error message ( e.g. "Illegal SHARE operation on reading from drive X" ) appears. The programs then continue to run in the normal way. Alternatively, you can set the "read-only" attribute with the DOS command ‘attrib +r simo.exe’ or ‘attrib +r tdep.exe’. However, this attribute must be replaced before you can delete this two files. ( use parameter -r )

As follows, a system configuration should look approximately :

Example of a CONFIG.SYS :

rem *** load high : DISPLAY.SYS ***
DEVICEHIGH=C:\WIN98\COMMAND\display.sys con=(ega,,1)
rem *** 40 MByte RAM Disk with 64 MByte main memory ***

Example of an AUTOEXEC.BAT :

rem *** it's better you don't load mouse ***
mode con codepage prepare=((850) C:\WIN98\COMMAND\ega.cpi)
mode con codepage select=850
rem *** KEYB do not load high ***
keyb gr,,C:\WIN98\COMMAND\keyboard.sys
rem C:\WIN98\COMMAND\SHARE.EXE /L:500 /F:5100
mode LPT1: ,,E

Measuring errors with PDM protocols, pulse width measuring or synchronous PCM protocols
with the use of a mouse :

With pulse duration modulation or strong burden of the PC, time errors can occur, if the mouse is moved. In order to avoid this, no mouse driver should be loaded.

Is a driver already loaded, a Logitech driver for example, you can unload this driver by the following command :


After that start the program LIAN.

with disk access :

Tolerance errors can occur with higher baud rates ( 1200 Baud or more ) during the record of pulse duration modulated data while writing to the hard disk. It is caused on a too slow disk. A RAM drive can be of help because it allows the extension memory to be used like a hard disk. The RAMDRIVE.SYS driver must be included in the CONFIG.SYS for this purpose. A typical call might be :


Here, 2.2 MByte RAM drive is installed in the extension memory. DOS assigns a free drive letter for this, for instance 'E:', under which this disk can be accessed. The new drive designation can then be entered in LIAN in the menu item <Setting><RAM drive>.

The program SIMO now automatically uses the specified virtual drive in the main memory while recording. The two files ( protocol- and archive file ) are copied to their directories on the hard disk only after quitting the program.

Program package LIAN and Windows 95 / Windows 98

It is still valid that SIMO as real time application should not run under Windows. Multi-tasking causes measuring errors with all protocols being based on pulse width measuring ( PDM, synchronous PCM ). With pure asynchronous PCM protocols, using the UART you can operate in the MS-DOS window of WINDOWS without any problems.


MAYR Software

Wuerzburger Ring 39,  D 91056 Erlangen


LIAN DOS Protocol Simulator and Analyzer
© Copyright 1991, 1996, 2001, 2006-2010 by Werner Mayr. All Rights reserved.