Hi
Thanks for responding. There seems to be no example for this particular board ( B-L475E-IOT01A1), and so I used the DFSM audio record example for the STM32L476-DISCOVERY board as reference.
I got the audio out of the board through a tcp socket ( after connecting to it to wifi)), and dumped to a a wav file.
My config is such -
- channel 1 and channel 2 are activated with SPI clock
- channel-1 feeds filter0, and chaneel-2 feeds filter 1.
- regular conversion with DMA enabled.
Here is my init of channel 2 which gets i/p from PE7 and gives clkout at PE9
hdfsdm1_channel2.Instance = DFSDM1_Channel2;
hdfsdm1_channel2.Init.OutputClock.Activation = ENABLE;
hdfsdm1_channel2.Init.OutputClock.Selection = DFSDM_CHANNEL_OUTPUT_CLOCK_AUDIO;
hdfsdm1_channel2.Init.OutputClock.Divider = 4;
hdfsdm1_channel2.Init.Input.Multiplexer = DFSDM_CHANNEL_EXTERNAL_INPUTS;
hdfsdm1_channel2.Init.Input.DataPacking = DFSDM_CHANNEL_STANDARD_MODE;
hdfsdm1_channel2.Init.Input.Pins = DFSDM_CHANNEL_SAME_CHANNEL_PINS;
hdfsdm1_channel2.Init.SerialInterface.Type = DFSDM_CHANNEL_SPI_FALLING;
hdfsdm1_channel2.Init.SerialInterface.SpiClock = DFSDM_CHANNEL_SPI_CLOCK_INTERNAL;
hdfsdm1_channel2.Init.Awd.FilterOrder = DFSDM_CHANNEL_SINC1_ORDER;
hdfsdm1_channel2.Init.Awd.Oversampling = 10;
hdfsdm1_channel2.Init.Offset = 0;
hdfsdm1_channel2.Init.RightBitShift = 2;
if (HAL_DFSDM_ChannelInit(&hdfsdm1_channel2) != HAL_OK)
{
Error_Handler();
}
Similar config for channel 1, as above. Below is filter 1 receiving feed from channel 2
hdfsdm1_filter1.Instance = DFSDM1_Filter1;
hdfsdm1_filter1.Init.RegularParam.Trigger = DFSDM_FILTER_SW_TRIGGER;
hdfsdm1_filter1.Init.RegularParam.FastMode = ENABLE;
hdfsdm1_filter1.Init.RegularParam.DmaMode = ENABLE;
hdfsdm1_filter1.Init.FilterParam.SincOrder = DFSDM_FILTER_SINC3_ORDER;
hdfsdm1_filter1.Init.FilterParam.Oversampling = 64;
hdfsdm1_filter1.Init.FilterParam.IntOversampling = 1;
if (HAL_DFSDM_FilterInit(&hdfsdm1_filter1) != HAL_OK)
{
Error_Handler();
}
if (HAL_DFSDM_FilterConfigRegChannel(&hdfsdm1_filter0, DFSDM_CHANNEL_1, DFSDM_CONTINUOUS_CONV_ON) != HAL_OK)
{
Error_Handler();
}
if (HAL_DFSDM_FilterConfigRegChannel(&hdfsdm1_filter1, DFSDM_CHANNEL_2, DFSDM_CONTINUOUS_CONV_ON) != HAL_OK)
{
Error_Handler();
}
after receiving data into my int32 buffers here is how conversion is being done to int 16:
SendBuff[2*i] = (uint16_t)(SaturaLH((LeftRecBuff[i] >> 8), -32768, 32767));
SendBuff[(2*i)+1] = (uint16_t)(SaturaLH((RightRecBuff[i] >> 8), -32768, 32767));
SendBuff here is int16 buffer, which is then written on the socket, and LeftRecBuff/RightRecBuff, are int32 buffers where recorded samples are stored.
I am also attaching a dump of the wav data that I got from the recording.
