Siemens SIMATIC ET 200SP Manual page 60

Data exchange between the user program and AS-i slaves
7.3 AS-i analog values and transparent / digital values more than 4 bits in length are transferred
Examples / notes on reading this table:
The subsequent table shows the assignment of analog values to the respective analog
slaves.
For additional information, refer to the operating instructions of the slaves.
Table 7- 10 Address range for the analog values of an AS-i slave
Byte no. (start address + offset)
Analog A/B slaves with 2 channels only reserve half the address range. A slaves occupy
bytes 0 to 3 and B slaves bytes 4 to 7.
Examples of the configuration:
1. Configuration:
Analog slaves have the AS-i addresses 1 to 6.
You use data record 140 and enter 48 as data record length.
2. Configuration:
1 analog slave with AS-i address 7 is used.
You use data record 141 and enter 24 as data record length. Only bytes 16 to 23 are
relevant.
3. Configuration:
The full address range for 31 analog slaves is used.
You use data record 140 and enter 224 as data record length. You can then address
analog slaves 1 to 28.
For the remaining analog slaves 29 to 31, you use data record 147 in a second job and
enter 24 as data record length.
4. Configuration:
Analog slaves have the addresses 29 to 31.
You use data record 147 and enter 24 as data record length.
Mixed access:
● Configuration:
You want to access slaves 1 to 12 using I/O commands and slaves 13 to 31 using data
records.
You use data record 143 for slaves 13 to 31.
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Start address + 0
Start address + 1
Start address + 2
Start address + 3
Start address + 4
Start address + 5
Start address + 6
Start address + 7
Analog value channel
Channel 1 / high byte
Channel 1 / low byte
Channel 2 / high byte
Channel 2 / low byte
Channel 3 / high byte
Channel 3 / low byte
Channel 4 / high byte
Channel 4 / low byte
AS-Interface master CM AS-i Master ST (3RK7137-6SA00-0BC1)
Manual, 07/2017, A5E02655262020A/RS-AD/004