16 ac’97 controller status register – Rainbow Electronics AT91CAP9S250A User Manual
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6264A–CAP–21-May-07
AT91CAP9S500A/AT91CAP9S250A
37.7.16
AC’97 Controller Status Register
Register Name:
AC97C_SR
Access Type:
Read-only
WKUP and SOF flags in AC97C_SR register are automatically cleared by a processor read operation.
• SOF: Start Of Frame
0: No Start of Frame has been detected since the last read of the Status Register.
1: At least one Start of frame has been detected since the last read of the Status Register.
• WKUP: Wake Up detection
0: No Wake-up has been detected.
1: At least one rising edge on SDATA_IN has been asynchronously detected. That means AC’97 Codec has notified a
wake-up.
• COEVT: CODEC Channel Event
A Codec channel event occurs when AC97C_COSR AND AC97C_COMR is not 0. COEVT flag is automatically cleared
when the channel event condition is cleared.
0: No event on the CODEC channel has been detected since the last read of the Status Register.
1: At least one event on the CODEC channel is active.
• CAEVT: Channel A Event
A channel A event occurs when AC97C_CASR AND AC97C_CAMR is not 0. CAEVT flag is automatically cleared when the
channel event condition is cleared.
0: No event on the channel A has been detected since the last read of the Status Register.
1: At least one event on the channel A is active.
• CBEVT: Channel B Event
A channel B event occurs when AC97C_CBSR AND AC97C_CBMR is not 0. CBEVT flag is automatically cleared when the
channel event condition is cleared.
0: No event on the channel B has been detected since the last read of the Status Register.
1: At least one event on the channel B is active.
• CCEVT: Channel C Event
A Channel C event occurs when AC97C_CCSR AND AC97C_CCMR is not 0. CCEVT flag is automatically cleared when
the channel event condition is cleared.
0: No event on Channel C has been detected since the last read of the Status Register.
1: At least one event on Channel C is active.
31
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28
27
26
25
24
–
–
–
–
–
–
–
–
23
22
21
20
19
18
17
16
–
–
–
–
–
–
–
–
15
14
13
12
11
10
9
8
–
–
–
–
–
–
–
–
7
6
5
4
3
2
1
0
–
–
CCEVT
CBEVT
CAEVT
COEVT
WKUP
SOF