51.9.7 Tx Serializer Control

Name: TXCTRL
Offset: 0x20
Reset: 0x00000000
Property: Enable-Protected, Write-Protection

Bit 3130292827262524 
       DMAMONO 
Access R/WR/W 
Reset 00 
Bit 2322212019181716 
 SLOTDIS7 SLOTDIS6 SLOTDIS5 SLOTDIS4 SLOTDIS3 SLOTDIS2 SLOTDIS1 SLOTDIS0  
Access R/WR/WR/WR/WR/WR/WR/WR/W 
Reset 00000000 
Bit 15141312111098 
 BITREVEXTEND[1:0]WORDADJ DATASIZE[2:0] 
Access R/WR/WR/WR/WR/WR/WR/W 
Reset 0000000 
Bit 76543210 
 SLOTADJ  TXSAMETXDEFAULT[1:0]   
Access R/WR/WR/WR/W 
Reset 0000 

Bit 25 – DMA Single or Multiple DMA Channels

This bit selects whether even-numbered and odd-numbered slots use separate DMA channels or the same DMA channel.

DMANameDescription
0x0SINGLESingle DMA channel
0x1MULTIPLEOne DMA channel per data channel

Bit 24 – MONO Mono Mode.

MONONameDescription
0x0STEREONormal mode
0x1MONOLeft channel data is duplicated to right channel

Bits 16, 17, 18, 19, 20, 21, 22, 23 – SLOTDISx  Slot x Disabled for this Serializer [x=7..0]

This field allows disabling some slots in each transmit frame:

ValueDescription
0Slot x is used for data transfer.
1Slot x is not used for data transfer and will be output as specified in the TXDEFAULT field.

Bit 15 – BITREV Data Formatting Bit Reverse

This bit allows changing the order of data bits in the word in the Formatting Unit.

BITREVNameDescription
0x0MSBITTransfer Data Most Significant Bit (MSB) first (default for I2S protocol)
0x1LSBITTransfer Data Least Significant Bit (LSB) first

Bits 14:13 – EXTEND[1:0] Data Formatting Bit Extension

This field defines the bit value used to extend data samples in the Formatting Unit.

EXTEND[1:0]NameDescription
0x0ZEROExtend with zeros
0x1ONEExtend with ones
0x2MSBITExtend with Most Significant Bit
0x3LSBITExtend with Least Significant Bit

Bit 12 – WORDADJ Data Word Formatting Adjust

This field defines left or right adjustment of data samples in the word in the Formatting Unit. for details.

WORDADJNameDescription
0x0RIGHTData is right adjusted in word
0x1LEFTData is left adjusted in word

Bits 10:8 – DATASIZE[2:0] Data Word Size

This field defines the number of bits in each data sample. For 8-bit compact stereo, two 8-bit data samples are packed in bits 15 to 0 of the DATAm register. For 16-bit compact stereo, two 16-bit data samples are packed in bits 31 to 0 of the DATAm register.

DATASIZE[2:0]NameDescription
0x03232 bits
0x12424 bits
0x22020 bits
0x31818 bits
0x41616 bits
0x516C16 bits compact stereo
0x688 bits
0x78C8 bits compact stereo

Bit 7 – SLOTADJ Data Slot Formatting Adjust

This field defines left or right adjustment of data samples in the slot.

SLOTADJNameDescription
0x0RIGHTData is right adjusted in slot
0x1LEFTData is left adjusted in slot

Bit 4 – TXSAME Transmit Data when Underrun.

TXSAMENameDescription
0x0ZEROZero data transmitted in case of underrun
0x1SAMELast data transmitted in case of underrun

Bits 3:2 – TXDEFAULT[1:0] Line Default Line when Slot Disabled

This field defines the default value driven on the SDn output pin during all disabled Slots.

TXDEFAULT[1:0]NameDescription
0x0ZEROOutput Default Value is 0
0x1ONEOutput Default Value is 1
0x2Reserved
0x3HIZOutput Default Value is high impedance