Intel PXA255, Developer'S Manual

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14-12 Intel® PXA255 Processor Developer’s Manual
Inter-Integrated-Circuit Sound (I2S) Controller
14.6.4 Serial Audio Clock Divider Register (SADIV)
SADIV, shown in Table 14-8 , is used for generating six different BITCLK frequencies and hence
six different sampling frequencies.
Table 14-7. SASR0 Bit Definitions
Physical Address
0x4040_000C
Serial Audio Controller I
2
S/MSB-
Justified Status Register
I
2
S Controller
Bit 31 30 29 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
reserved RFL TFL
re
se
rv
e
d
RO
R
TU
R
RF
S
TFS
BSY
RN
E
TN
F
Reset 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1
Bits Name Description
31:16 — reserved
15:12 RFL Receive FIFO Level: number of entries in Receive FIFO
11:8 TFL Transmit FIFO Level: number of entries in Transmit FIFO
7 — reserved
6 ROR
Receive FIFO Overrun:
0 = Receive FIFO has not experienced an overrun
1 = I
2
S attempted data write to full Receive FIFO (Interruptible)
Can interrupt processor if bit6 of Serial Audio Interrupt Mask Register is set.
Cleared by setting bit 6 of Serial Audio Interrupt Clear Register.
5 TUR
Transmit FIFO Under-run:
0 = Transmit FIFO has not experienced an under-run
1 = I
2
S attempted data read from an empty Transmit FIFO
Can interrupt processor if bit 5 of Serial Audio Interrupt Mask Register is set.
Cleared by setting bit 5 of Serial Audio Interrupt Clear Register.
4 RFS
Receive FIFO Service Request:
0 = Receive FIFO level below RFL threshold, or I
2
S disabled
1 = Receive FIFO level is at or above RFL threshold.
Can interrupt processor if bit 4 of Serial Audio Interrupt Mask Register is set.
Cleared automatically when # of Receive FIFO entries < (RFTH + 1).
3 TFS
Transmit FIFO Service Request:
0 = Transmit FIFO level exceeds TFL threshold, or I
2
S disabled
1 = Transmit FIFO level is at or below TFL threshold
Can interrupt processor if bit 3 of Serial Audio Interrupt Mask Register is set.
Cleared automatically when # of Transmit FIFO entries >= (TFTH + 1).
2 BSY
I
2
S Busy:
0 = I
2
S is idle or disabled
1 = I
2
S currently transmitting or receiving a frame
1 RNE
Receive FIFO not empty:
0 = Receive FIFO is empty
1 = Receive FIFO is not empty
0 TNF
Transmit FIFO not full:
0 = Transmit FIFO is full
1 = Transmit FIFO is not full