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AT32F413
Series Reference Manual
2022.06.27
Page 169
Rev 2.00
Programmable audio protocol
─
I
2
S Philips standard
─
MSB-aligned standard (left-aligned)
─
LSB-aligned standard (right-aligned)
─
PCM standard (long or short frame)
DMA transfer
Main peripheral clock with a fixed frequence of 256 x Fs (audio sampling frequency)
13.3.2 Operation mode selector
When used as I
2
S selector, the SPI interface offers multiple operation modes for selection, namely, slave
device transmission, slave device reception, master device transmission and master device reception.
This is done by software configuration.
Slave device transmission:
Set the I2SMSEL bit, and OPERSEL[1:0] =00, the I
2
S will work in slave device transmission mode.
Figure 13-14
I
2
S slave device transmission
I2S master
CK
SD
WS
I2S slave
CK
SD
WS
Slave device reception:
Set the I2SMSEL bit, and OPERSEL[1:0]=01, the I
2
S will work in slave device reception mode.
Figure 13-15
I
2
S slave device reception
I2S master
CK
SD
WS
I2S slave
CK
SD
WS
Master device transmission:
Set the I2SMSEL bit, and OPERSEL[1:0]=10, the I
2
S will work in master device transmission mode.