In this thesis a process control with GPRS had to be developed. The setting of tasks demanded a server that controlled 8 digital inputs and 8 digital outputs on the client side. A demo application should also be developed. However, the problem was that we couldn?t find a good demo application. We therefore decided to make an universal print. In addition to the 8 digital in- and outputs we developed 8 analogue inputs.

The whole system works as described below. The client is equipped with GSM modem that is GPRS suitable. We used the GM862-GPRS modem which is equipped with an included TCP/IP stack. With this stack a TCP/IP connection to a server can easily be done. The client makes a GPRS connection with the network provider over the GSM net. From there the connection goes further with the help of a TCP/IP protocol to the internet and finally to the Server. The included TCP/IP stack does all the work which is needed to do this connection over the internet. We have to build the connection from the client to the server. This because the IP number of the GSM modem is dynamically created by our network provider Swisscom. So we have no chance to start the connection from the server.

Our task was now to develop an application that is able to build a TCP/IP server. This application had to be able to make those 8 digital in- and outputs and the 8 analogue inputs accessible for a user. This server was programmed with Delphi.

Furthermore, we had to develop a print to connect the micro controller with the GSM modem for the client. The additional hardware, like for example port drivers, was also placed on that print. The software for the micro controller had to be able to start and control the GSM modem as well as to control the in- and outputs and send and receive commands to and from the server.

The whole System works quite well and its reliable. We were not only able to fulfil the whole setting of tasks, but we were also able to amend them with the analogue inputs.