Approximately 100 Volvo dealers running S/36 applications were involved in our modernization project. These locations were using both a mixture of legacy S/36 and AS/400 applications running on 50 AS/400’s to support established business processes. In 2002/2003 we looked around for software solutions to replace these existing business systems but in the end decided the best and most cost effective solution was to modernize rather than replace our S/36 legacy business applications to run on the iSeries.

     The steps involved in the upgrade process were: first to convert and upgrade the S/36 code to native mode and ILE, followed by refacing the green screens and integrating the business applications with external applications such as Microsoft office. This approach resulted in extending the functionality of the original applications and also importantly allowed us to be more readily able to meet any subsequent development needs that may arise from our dealer organization in the future.

     The initial task of converting and upgrading the S/36 code to ILE and native mode on the iSeries was vital to the modernization process and we considered this a major first step. The original S/36 applications used by our dealers had been initially developed in 1984 and had subsequently evolved over the next 14 year period. The code had been maintained by several teams over the years and for the main part had been coded in S/36 RPGII which later ran in the S/36 environment on the AS/400. To successfully complete the initial phase of the modernization project we needed to convert the following number of items: 280 S/36 data files to DB2 and DDS including a dozen or so multi-record type files; 400 S/36 $SFGR screen members to DDS; 720 OCL procedures to ILE CLP; 535 RPGII programs to ILE RPG (RPG IV). These also had to be integrated with approximately 215 pre-existing native mode display files and 344 native CL programs. A further 557 RPG III (RPG/400) programs needed to be converted to RPG IV (ILE) to complete the first phase of the project.

     To successfully complete this crucial first step in the modernization process we choose the software tool TARGET/400 from Excel Program Inventions. Using TARGET/400 we were able to build an external native DB2 database. We found TARGET/400 to be a great help in this area as it gave us the capability to extract the internal file definitions from the program code and additionally build up a comprehensive field reference file. It also automatically detected and allowed us to correct any field naming discrepancies in the different file definitions and it solved the problem of converting multi-format files too. The end result was a native DB2 database which implemented proper field naming standards. The tool also migrated our S/36 $SFGR screen specifications to DDS without problems. We additionally found the tool indispensable in converting our OCL procedures to CLP and found the code it produced was both consistent and robust. Here, yet again TARGET/400 saved us a great deal of time and effort because without it we would have faced the impractical task of rewriting every OCL procedure manually. The tool automatically converted our RPGII and RPGIII programs to RPGIV. This process initially leaves the file descriptions in the resulting RPG program code as program described until such times as you use TARGET/400 to globally or selectively externalize them. We decided the best approach for Volvo was to get the modernized applications up and running first and as quickly as possible, then at a later date as time permitted selectively use TARGET/400's file externalization feature to replace the internally defined RPG file descriptions and standardize the field names within the code. This task we decided was best handled during the maintenance cycle as this would result in our most regularly maintained files and programs being updated first followed by the others later, the desired outcome.

     The refacing of the green screens was done by means of newlook. A dynamic refacing product from looksoftware. Besides refacing, this product can also be used to integrate applications with the outside world, for example to connect to other DB’s, web services and office environments, etc.

     Using TARGET/400 from Excel Program Inventions and a refacing and integration product like newlook from looksoftware extended the life of our S/36 legacy applications. We found the advantages of this approach to be clear cut. Now our end users will not have to learn or be taught a new application and our "hidden" business rules developed and perfected over time will continue to serve Volvo well into the future. Our development team can now use their time and energy to extend and enhance our business applications as opposed to needlessly rewriting them or trying to make a new software package "fit". All in all we have found our S/36 modernization project using TARGET/400 on the iSeries and Newlook to be a great success.

 
July 2004.

For more information on TARGET/400 please visit http://www.epi-software.com