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The TPIU supports up to two ATB ports.
The ATB1 and ATB2 parameters provide the following configuration options:
|ATB2 = 0 and ATB1 = 0||Illegal combination|
|ATB2 = 0 and ATB1 = 1||ATB port 1 present|
|ATB2 = 1 and ATB1 = 0||ATB port 2 present|
|ATB2 = 1 and ATB1 = 1||Both ATB port 1 and 2 present|
In a system, Arm® recommends that the ITM is connected to ATB port 1 and an ETM is connected to ATB port 2.
If your implementation requires no trace support, then the TPIU might not be present.
The following figure shows the component layout of the TPIU for both configurations.
If only one ATB slave port is present, it is assigned to ATB interface 1 and ATB interface 2 is removed. If ATB slave ports 1 and 2 are present, they are assigned to ATB interface 1 and 2 respectively.