The AS-i bus is independently managed by the master. This exchanges data on each cycle with each slave device configured on the bus (in ascending order of slave address number).
Scanning time t represents the exchange time between the master and n slaves (31 maximum).
So, for:
-
t = 156 microseconds x (n+2), if n < 31,
-
t = 156 microseconds x (n+1), if n = 31.
So the scanning time cannot exceed 5 ms.
The response time T represents the AS-i cycle time.
This includes:
The table below shows three examples of T response time for a PLC task lasting 10 ms, 30 ms, and 60 ms.
This T time is for a bus loaded with 31 slaves operating normally with no link faults.
|
PLC task
|
Typical response time
|
Maximum response time
|
|
10 ms
|
35 ms
|
56 ms
|
|
30 ms
|
65 ms
|
96 ms
|
|
60 ms
|
110 ms
|
156 ms
|
