7.3.6 Units of indicators
Indicator units are coded as follows:
At address 3000, one can read hexadecimal value AAAA permanently, which allows
checking the proper operating of the transfer connection.
Indicator units are available in the address range from 3000 to 3256, and sorted
according to the table below:
Hexadecimal AAAA, set value
Logical status of indicator #1
Logical status of indicator #2
Logical status of indicator #256