EC32 - General Information

Its kernel performs the internal administration, provides interfaces for intertask- and driver-communication as well as for PLC?s like Siemens S5 , S7, and Modicon (ModBus+). Online diagnostic is possible through 3 different media: trace-messages are sent to a logfile, an external serial COM-port and for interactive operating and monitoring to a service window on the console.

New: The connectivity to PLC has been expanded to the PROFIBUS-FMS. This communication protocol is available not only with Siemens S7 PLC's but also with other brands.

Very often we were tied into discussions why we still are using a so called outdated DOS based operating system and not Windows NT or UNIX. We have very good reasons not to do as asked.

Certain areas of the system software and also certain applications require realtime performance and do not allow latency times which still do exist in those other multi-tasking systems. Of course there are measures also available with NT to overcome those latencies. Nevertheless, in many cases this requires to write drivers, which can execute in ring 0 of the OS. With EC32 we can guarantee to provide our customers with a implementation of a new driver in less than a week, analyzed, coded, tested and released for productional usage. If you know somebody who could write and release a driver for NT ring 0 in the same amount of time, please let us know. Please check also : Why not Windows?

Another reason is the maintainabilty. Every hardware is supposed to fail at some time and requires a new software installation.

One question: how long would it take to re-install for example a Windows-NT system including the application software and get it back to opertion?

With EC32 we guarantee to have the entire system re-installed in less than 15 minutes, of which the DOS OS installation takes 10 minutes. We believe, that this could save valuable production time. Furthermore, not each company has maintenance personal ready and skilled enough to handle NT or UNIX systems.

By the way: EC32 is not a DOS operating system. It is a summary of system tools and applications, which are using a real-time, protected mode (up to 64 Mega-Bytes of memory) and re-entrant multi-tasking kernel!

Finally its also a matter of cost. Using NT you'll need at least a OS license which is not very expensive, but if you got multiple installations, it adds up.

By the way: Due to the large pool of existing applications we are able to guarantee the 'ready for installation' status of ANY new application based upon a Technical Specification within ONE WEEK!

Intertask communcation is done via a channel-concept provided by the system through mailboxes and semaphores. The current maximum number of channels is 1000. Up to 32 drivers may be configured and up to 8 interrupt-controlled serial ports are serviced concurrently. Interfacing with production control systems may be done by means of discrete I/O interfaces (32 DI and 32 DO)or an INTERBUS-S interface (255 DI, 255 DO)

Very often we were asked "Why do you use the unsecured UDP layer instead of the secure TCP"? There are different reasons:

TCP requires to establish a connection between two sockets in the two adjacent host systems. The first development for network communication in this scenario was done using a 16 bit real mode platform by the name of ASA, which only had limited memory. It was found, that the ressources for that socket could not be re-gained after a connection was accidently interrupted and a new socket had to be created. If this was repeated several times, which is quite normal for an unattended system, the software was running out of memory. So Volkswagen had made the decision to use UDP for their internal FIS environment.

The overhead of TCP is much higher due to the security mechanisms and causes a lower overall troughput.

The most important reasons are found in the different implementation requirements. With TCP we have to define whether the driver will be a client OR a server. Using unattended systems on the other hand requires, that each system could close and re-open a connection at any time regardless, whether the connection was closed by controlled and pre-defined functions or was accidently interrupted due to power failures or simply because somebody pulled the connector.