SAM9G46_14 Datasheet, PDF (1091/1286 Pages) ATMEL Corporation – Atmel | SMART ARM-based Embedded MPU

43.8.8 AC97 Controller Channel A Status Register
Register Name:
Address:
AC97C_CASR
0xFFFAC028
Access Type: Read
-only
31
–
23
–
15
RXBUFF
7
–
30
–
22
–
14
ENDRX
6
–
29
–
21
–
13
–
5
OVRUN
28
–
20
–
12
–
4
RXRDY
27
–
19
–
11
TXBUFE
3
–
26
–
18
–
10
ENDTX
2
UNRUN
25
–
17
–
9
–
1
TXEMPTY
24
–
16
–
8
–
0
TXRDY
• TXRDY: Channel Transmit Ready
0: Data has been loaded in Channel Transmit Register and is waiting to be loaded in the Channel Transmit Shift Register.
1: Channel Transmit Register is empty.
• TXEMPTY: Channel Transmit Empty
0: Data remains in the Channel Transmit Register or is currently transmitted from the Channel Transmit Shift Register.
1: Data in the Channel Transmit Register have been loaded in the Channel Transmit Shift Register and sent to the codec.
• UNRUN: Transmit Underrun
Active only when Variable Rate Mode is enabled (VRA bit set in the AC97C_MR register). Automatically cleared by a pro-
cessor read operation.
0: No data has been requested from the channel since the last read of the Status Register, or data has been available each
time the CODEC requested new data from the channel since the last read of the Status Register.
1: Data has been emitted while no valid data to send has been previously loaded into the Channel Transmit Shift Register
since the last read of the Status Register.
• RXRDY: Channel Receive Ready
0: Channel Receive Holding Register is empty.
1: Data has been received and loaded in Channel Receive Holding Register.
• OVRUN: Receive Overrun
Automatically cleared by a processor read operation.
0: No data has been loaded in the Channel Receive Holding Register while previous data has not been read since the last
read of the Status Register.
1: Data has been loaded in the Channel Receive Holding Register while previous data has not yet been read since the last
read of the Status Register.
• ENDTX: End of Transmission for Channel A
0: The register AC97C_CATCR has not reached 0 since the last write in AC97C_CATCR or AC97C_CANCR.
1: The register AC97C_CATCR has reached 0 since the last write in AC97C_CATCR or AC97C_CATNCR.
SAM9G46 Series [DATASHEET]
Atmel-11028F-ATARM-SAM9G46-Datasheet_16-Oct-14
1091