STMicroelectronics STM32WLEx Reference Manual page 1211

RM0461
Bits 7:0 I2SDIV[7:0]: I2S linear prescaler
I2SDIV [7:0] = 0 or I2SDIV [7:0] = 1 are forbidden values.
Refer to
Note: These bits should be configured when the I2S is disabled. They are used only when the I2S is
in master mode.
They are not used in SPI mode.
Serial peripheral interface / integrated interchip sound (SPI/I2S)
Section 35.7.3 on page 1190.
RM0461 Rev 5 1211/1306
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