PNX17XX Datasheet, PDF (545/832 Pages) NXP Semiconductors – Connected Media Processor

Philips Semiconductors
Volume 1 of 1
PNX17xx Series
Chapter 16: Audio Input
3.13 Raw Mode
Apart from the usual I²S mode and the early mode, capture can also be enabled in
the raw mode. At every sample clock (SCK) the data bit(s) from each active channel
is capture along with the WS. This information is then formed as a byte. After four
such bytes are formed, the resulting 32-bit data is transferred to memory. Hence
every sample clock results in a byte of data for software to tear apart and manipulate.
The following table shows how the data bits, and the WS are sampled with respect to
the different channels and formed in to a byte that gets transferred to memory.
Table 9: Raw Mode Format of Input Data and Word Select
Bit 7 Bit 6
Bit 5
Bit 4
Bit 3
Bit2
Bit 1
Bit 0
0
0
0
SD[3] SD[2]
SD[1]
SD[0]
WS
4. Register Descriptions
The register descriptions for the Audio In block are given below. The base address for
the Audio In registers begins at offset 0x11 1000.
Table 10: Register Summary
Offset
Name
Description
0x11 1000
AI_STATUS
Provides status of Audio In components/situations.
0x11 1004
AI_CTL
Control register to configure Audio In options
0x11 1008
AI_SERIAL
Control register to configure Audio In serial timing and data options
0x11 100C
AI_FRAMING
Control register to configure data framing format
0x11 1010
Reserved
0x11 1014
AI_BASE1
Base address of buffer 1
0x11 1018
AI_BASE2
Base address of buffer 2
0x11 101C
AI_SIZE
The DMA Buffer size in samples
0x11 1020—1FF0
Reserved
0x11 1FF4
AI_PWR_DWN
Powerdown function. Implementation details not decided yet.
0x11 1FFC
AI_MODULE_ID
Module ID number, including major and minor revision levels
4.1 Register Table
Table 11: Audio (I²S) Input Ports Registers
Bit Symbol
Acces
s
Value
Description
Note: The clock frequency emitted by the AI_OSCLK output is set in registers that control the Clock block in the chip.
Offset 0x11 1000
AI_STATUS
31:5 Unused
-
4
BUF1_ACTIVE
R
1
1 = Buffer will be used for the next incoming sample.
0 = Buffer 2 will receive the next sample.
3
OVERRUN
R
0
An OVERRUN error has occurred i.e., software failed to provide an
empty buffer in time and 1 or more samples have been lost.
2
HBE
R
0
Bandwidth Error
PNX17XX_SER_1
Preliminary data sheet
Rev. 1 — 17 March 2006
© Koninklijke Philips Electronics N.V. 2006. All rights reserved.
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