4
This is sufficient to address 32 slaves� In normal operation, address 0 is not permitted, thus allowing 31 AS-i slaves to be operated� The address range is doubled
by using the data bit D3 as sixth bit for addressing, which enables the addressing
of 62 slaves�
For reasons of compatibility the message structure has not been changed�
Using the identification code, the master detects whether or not version 2�1 is
supported (ID code = 0A hex )� If it is a version 2�1 AS-interface slave, this slave
receives two additional identification codes (ID1 and ID2) which describe the
functionality of the slave� A special feature of these additional ID codes is that the
ID1 code can be written by the user�
If automatic addressing is used, these additional ID codes are also read and compared to those of the faulty slave�
Address 0 is only changed to the address of the faulty slave if all ID codes of the
new slave correspond to those of the old slave�
AS-interface slaves which do not support version 2�1 can be used together with
AS-interface slaves which support version 2�1�
The addressing unit enables the writing of identification code ID1� If the ID code
ID1 is changed by the user and automatic addressing is used, ensure that the
correct ID code 1 was stored in the slave before installing the new slave�
With version 2�1 AS-i slaves, data bit D3 of the output data is used to differentiate
between A and B slaves� A version 2�1 AS-interface slave thus supports 4 bits of
input data and 3 bits of output data� When fully expanded, up to 248 bits of input
data and 186 bits of output data are available�
As of version 2�1, an address can be assigned twice, e�g� address 15A and 15B�
This means that the data for slave 15A is written and read in the first cycle and
the data for slave 15B in the following cycle, followed again by slave 15A� This
increases the cycle time for slaves A and B to maximum 10 ms� The cycle time of
conventional slaves remains unchanged as these are scanned in every cycle�
If an AS-interface slave is used which does not support version 2�1, an address
may be assigned only once�
Structure of the addressing unit 4
The battery for AC1154 is charged when delivered� It is, however, possible that
the battery charge is inadequate due to long storage times and self-discharge�
This is indicated by a battery symbol on the display� If this symbol is displayed, the