Introduction
Display terminal
The display terminal has an illuminated, low-reflection LC display with two lines of 16 characters. It can be used, for example, for displaying status messages or diagnostic information. A non-resettable operating hour meter is integrated and can be displayed and also read out via the controller.
Via the user program dynamic and static application-specific texts can be displayed, e.g. “Production counter: (count value)”. If the output text is longer than 16 characters, the terminal automatically switches to scrolling text mode. Two special characters can be defined via a 5x8 pixel matrix.
The statuses of the navigation switch – up, down, left, right and Enter – are transmitted to the controller as binary variables and can be used to control the display.
4 x 32-bit timer values are available. They are activated through 4 bits in the process data. If the flag is set the time value is incremented each second. The time values can be reset.
This can be used, for example, to count the time for which a machine was in production or in an error state.
In addition, 4 x 32-bit counters are available. They are activated through 4 bits in the process data and are incremented in the event of a positive edge.
The data for the four timers, the four counters and the operating hours counter are saved on the terminal every 15 minutes. In addition, the data can be saved manually when the system is shut down. If this feature is not used, the maximum inaccuracy is 15 minutes.
The operating hours counter is specified with a resolution of 1 second per digit. With 32 bits this means that an overflow won't occur for 139 years. The EEPROM for storing the counter, timer and operating hours counter data can hold more than 100 years’ worth of data, based on 15-minutes write cycles.