ST STM32F446 Series User Manual

RM0390 Rev 4 955/1328
RM0390 Serial audio interface (SAI)
973
The OVRUDR flag is cleared when COVRUDR bit is set in the SAI_xCLRFR register.
Figure 368. Overrun detection error
Underrun
An underrun may occur when the audio block in the SAI is a transmitter and the FIFO is
empty when data need to be transmitted. If an underrun is detected, the slot number for
which the event occurs is stored and MUTE value (00) is sent until the FIFO is ready to
transmit the data corresponding to the slot for which the underrun was detected (refer to
Figure 369). This avoids desynchronization between the memory pointer and the slot in the
audio frame.
The underrun event sets the OVRUDR flag in the SAI_xSR register and an interrupt is
generated if the OVRUDRIE bit is set in the SAI_xIM register. To clear this flag, set
COVRUDR bit in the SAI_xCLRFR register.
The underrun event can occur when the audio sub-block is configured as master or slave.
Figure 369. FIFO underrun event
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ST STM32F446 Series Specifications

General

Brand	ST
Model	STM32F446 Series
Category	Microcontrollers
Language	English