Figure 7.
Boot-mode switch SW1
7.6
Audio
7.6.1
Description
The CS42L51-CNZ codec is connected through an SAI interface to the STM32MP157x microcontroller. This
component supports the TDM feature of the SAI port. The TDM feature offers STM32MP157x the capability to
stream stereo audio channels.
7.6.2
Operating voltage
The audio codec has two power supplies:
•
VL, connected to the 3.3 V provided by the STPMIC1
•
1V8_AUDIO, dedicated 1.8 V source provided by the STPMIC1
7.6.3
Audio codec interface
Audio codec interfacing is performed through the SAI2 and I2C1 interfaces of the STM32MP157x.
describes the I/O configuration of the audio codec interface.
Table 6.
I/O configuration for the audio interface
I/O
Configuration
PG9
PG9 used as AUDIO RESETN (active LOW)
PE0
PE0 used as SAI2_MCLKA
PF11
PF11 used as SAI2_SDB shared with GPIO expansion
PI7
PI7 used as SAI2_FSA shared with GPIO expansion
PI5
PI5 used as SAI2_SCKA shared with GPIO expansion
PI6
PI6 used as SAI2_SDA shared with GPIO expansion
PD12
PD12 used as I2C1_SCL shared between USB, DSI, HDMI
PF15
PB7 used as I2C1_SDA shared between USB, DSI, HDMI
7.6.4
Headphone outputs
The STM32MP157A-DK1 and STM32MP157C-DK2 Discovery kits can drive a stereo headphone. The
STM32MP157x sends the stereo audio channels to the codec via its SAI2 TDM port. The codec converts the
digital audio stream to stereo analog signals. It then boosts them for direct drive of the headphone connected to
the CN10 3.5 mm stereo jack receptacles on the board.
UM2534
Audio
UM2534
-
Rev 1
page 13/47
