Siemens DP/AS-Interface Link 20E, Руководство пользователя

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Data Exchange Between the DP Master and AS-i Slave
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DP/AS-Interface Link 20E
Release 11/2002
C79000-G8976-C138–04
Table 2-4 Address Area for the Analog Values of an AS-i Slave
Byte no. (start a offset) Analog value channel
Start a 0 Channel 1 / high byte
Start a 1 Channel 1 / low byte
Start a 2 Channel 2 / high byte
Start a 3 Channel 2 / low byte
Start a 4 Channel 3 / high byte
Start a 5 Channel 3 / low byte
Start a 6 Channel 4 / high byte
Start a 7 Channel 4 / low byte
Examples:
1. Configuration: Analog slaves have the AS-i addresses 1–6
You use data record 140 and specify 48 as the data record length.
2. Configuration: 1 analog slave with AS-i address 7 is used
You use data record 141 and specify 24 as the data record length.
3. Configuration: The entire address range for 31 analog slaves is used
You use data record 140 and specify 224 as the data record length. This covers
analog slaves 1–28.
For the other analog slaves 29–31, you use data record 147 in a second job
and specify 24 as the data record length.
4. Configuration: Analog slaves are in the address range 29–31
You use data record 147 and specify 24 as the data record length.
Representation of the Analog Values
According to slave profile 7.3 or 7.4, the analog values are interpreted as 16-bit
values in two’s compliment
For further information regarding the range of values, the measurement range and
the accuracy please refer to the relevant documentation of the analog slaves.