UM10237_2 © NXP B.V. 2008. All rights reserved.
User manual Rev. 02 — 19 December 2008 614 o f 792
NXP Semiconductors UM10237
Chapter 23: LPC24XX I2S interface
[1] Reset Value reflects the data stored in used bits only. It does not include reserved bits content.
5.1 Digital Audio Output Register (I2SDAO - 0xE008 8000)

The I2SDAO register controls the operation of the I2S transmit channel. The function of

bits in DAO are shown in Table23–532.

5.2 Digital Audio Input Register (I2SDAI - 0xE008 8004)

The I2SDAI register controls the operation of the I2S receive channel. The function of bits

in DAI are shown in Table23–533.

I2SIRQ Interrupt Request Control Register. Contains bits
that control how the I2S interrupt request is
generated.
R/W 0xE008 801C
I2STXRATE Transmit bit rate divider. This register
determines the I2S transmit bit rate by specifying
the value to divide pclk by in order to produce
the transmit bit clock.
R/W 0xE008 8020
I2SRXRATE Receive bit rate divider. This register determines
the I2S receive bit rate by specifying the value to
divide pclk by in order to produce the receive bit
clock.
R/W 0xE008 8024
Table 531. Summary of I2S registers
Name Description Access Reset
Value [1] Address
Table 532: Digital Audio Output register (I2SDAO - address 0xE008 8000) bit description
Bit Symbol Value Description Reset
Value
1:0 wordwidth Selects the number of bytes in data as follows: 01
00 8 bit data
01 16 bit data
10 Reserved, do not use this setting
11 32 bit data
2 mono When one, data is of monaural format. When zero, the
data is in stereo format. 0
3 stop Disables accesses on FIFOs, places the transmit
channel in mute mode. 0
4 reset Asynchronously reset the transmit channel and FIFO. 0
5 ws_sel When 0 master mode, when 1 slave mode. 1
14:6 ws_halfperiod Word select half period minus one, i.e. WS 64clk period
-> ws_halfperiod = 31. 0x1F
15 mute When true, the transmit channel sends only zeroes. 1