Posted on November 22, 2017 at 03:17I am trying to configure I2S3 in Fullduplex Master RX mode, 48KHz sample rate. Hal Configuration is as shown below
hAudioFDI2s
.
Init
.
AudioFreq
=
AudioFreq
;
hAudioFDI2s
.
Init
.
ClockSource
=
I2S_CLOCK_PLL
;
hAudioFDI2s
.
Init
.
CPOL
=
I2S_CPOL_LOW
;
hAudioFDI2s
.
Init
.
DataFormat
=
I2S_DATAFORMAT_16B
;
hAudioFDI2s
.
Init
.
MCLKOutput
=
I2S_MCLKOUTPUT_DISABLE
;
hAudioFDI2s
.
Init
.
Mode
=
I2S_MODE_MASTER_RX
;
hAudioFDI2s
.
Init
.
Standard
=
I2S_STANDARD
;
hAudioFDI2s
.
Init
.
FullDuplexMode
=
I2S_FULLDUPLEXMODE_ENABLE
;
I2S PLLs are configured successfully for 48KHz sample rate, I confirmed it by probing the WS and BCLK pins
WS: 48KHz
Bit Clock: 3.072Mhz ( 48 * 16bit * 2ch*)*2 (for extended mode) = 3.072KHz, and I have connected this to an external codec configured to receive I2S signals from ST.
However, the problem I am facing is I get distorted audio in only left channel. And above setup works well with the 16KHz no distortion in both channels. I confirmed the same behavior with different codec too. So, I don't think this is a misconfiguration in codec.
I am using DMA to transmit data over I2S
hdma_i2sRx
.
Init
.
Channel
=
DMA_CHANNEL_0;
hdma_i2sRx
.
Init
.
Direction
=
DMA_PERIPH_TO_MEMORY
;
hdma_i2sRx
.
Init
.
PeriphInc
=
DMA_PINC_DISABLE
;
hdma_i2sRx
.
Init
.
MemInc
=
DMA_MINC_ENABLE
;
hdma_i2sRx
.
Init
.
PeriphDataAlignment
=
DMA_PDATAALIGN_HALFWORD
;
hdma_i2sRx
.
Init
.
MemDataAlignment
=
DMA_MDATAALIGN_HALFWORD
;
hdma_i2sRx
.
Init
.
Mode
=
DMA_NORMAL
;
hdma_i2sRx
.
Init
.
Priority
=
DMA_PRIORITY_HIGH
;
hdma_i2sRx
.
Init
.
FIFOMode
=
DMA_FIFOMODE_ENABLE
;
hdma_i2sRx
.
Init
.
FIFOThreshold
=
DMA_FIFO_THRESHOLD_FULL
;
hdma_i2sRx
.
Init
.
MemBurst
=
DMA_MBURST_SINGLE
;
hdma_i2sRx
.
Init
.
PeriphBurst
=
DMA_PBURST_SINGLE
;
hdma_i2sRx
.
Instance
= DMA1_Stream0
Tx configuration:
hdma_i2s_ext_tx
.
Init
.
Channel
= DMA_CHANNEL_2
;
hdma_i2s_ext_tx
.
Init
.
Direction
=
DMA_MEMORY_TO_PERIPH
;
hdma_i2s_ext_tx
.
Init
.
PeriphInc
=
DMA_PINC_DISABLE
;
hdma_i2s_ext_tx
.
Init
.
MemInc
=
DMA_MINC_ENABLE
;
hdma_i2s_ext_tx
.
Init
.
PeriphDataAlignment
=
DMA_PDATAALIGN_HALFWORD
;
hdma_i2s_ext_tx
.
Init
.
MemDataAlignment
=
DMA_MDATAALIGN_HALFWORD
;
hdma_i2s_ext_tx
.
Init
.
Mode
=
DMA_NORMAL
;
hdma_i2s_ext_tx
.
Init
.
Priority
=
DMA_PRIORITY_HIGH
;
hdma_i2s_ext_tx
.
Init
.
FIFOMode
=
DMA_FIFOMODE_ENABLE
;
hdma_i2s_ext_tx
.
Init
.
FIFOThreshold
=
DMA_FIFO_THRESHOLD_FULL
;
hdma_i2s_ext_tx
.
Init
.
MemBurst
=
DMA_MBURST_SINGLE
;
hdma_i2s_ext_tx
.
Init
.
PeriphBurst
=
DMA_PBURST_SINGLE
;
hdma_i2s_ext_tx
.
Instance
=
DMA1_Stream5
;
I was wondering is there any known issues with the I2S3 in extended mode? or Am I configuring it wrongly?
Thank you,
Raj
#i2s-dma-audio #i2s-i2s2ext
