4. Error Cases
The bridge will display an error message when proper operation is not achieved.
There could be many reasons why audio streaming would not be effective.
4.1. Input Presence Rate Mismatch
The source ports are all sharing the same I2S clocks (MCLKI reference). Therefore, they
must also use the same Presence Rate.
When 2 or more source ports are not getting assigned the same Presence Rate, the
bridge will report an error and will not setup any data transmission. The error is shown on
the display main page.
I2S >ASRC24>SB>----
P01234567 OPR=n/a
II------ IPR=Error
Err: IPR mismatch...
To solve the problem, assign the proper Presence rate to the data channels attached to
the source ports.
4.2. Output Presence Rate Mismatch
The sink ports are all sharing the same I2S clocks (MCLKO reference). Therefore, they
must also use the same Presence Rate.
When 2 or more sink ports are not getting assigned the same Presence Rate, the bridge
will report an error and will not setup any data reception. The error is shown on the display
main page.
I2S >ASRC24>SB>SDO2
P01234567 OPR=Error
IIOO---- IPR=48k
Err: OPR mismatch...
To solve the problem, assign the proper Presence rate to the data channels attached to
the sink ports.
4.3. Incompatible Input and Output Presence Rate
The Presence Rate incompatibility only happens when the PLL operation is selected.
When the Input Presence Rate and the Output Presence Rate are leading to conflicting
PLL settings, the “!” symbol is displayed after OPR and IPR to indicate that the PLL could
not be set.
I2S >ASRC24>SB>SDO2
P01234567 OPR!192k
IIOO---- IPR!48k
Err: Incompatible PR
Running on external clocks will not have such limitations.
SLIMbus Audio Bridge User Manual V0,9 - Draft Version
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