DocID025202 Rev 7
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RM0365
Serial peripheral interface / inter-IC sound (SPI/I2S)
959
Figure 358. I
2
S Philips protocol waveforms (16/32-bit full accuracy)
Data are latched on the falling edge of CK (for the transmitter) and are read on the rising
edge (for the receiver). The WS signal is also latched on the falling edge of CK.
Figure 359. I
2
S Philips standard waveforms (24-bit frame)
This mode needs two write or read operations to/from the SPIx_DR register.
•
In transmission mode:
If 0x8EAA33 has to be sent (24-bit):
Figure 360. Transmitting 0x8EAA33
•
In reception mode:
If data 0x8EAA33 is received:
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