- LIS302DL: 3-axis accelerometer
- MP45DT02: digital microphone
- http://www.christoph-lauer.de/archives/11669
- https://www.theunterminatedstring.com/probing-pdm/
- http://www.st.com/content/ccc/resource/technical/document/application_note/ca/18/be/bb/f8/53/47/a5/DM00040808.pdf/files/DM00040808.pdf/jcr:content/translations/en.DM00040808.pdf
- CS43L22: audio DAC, speaker driver
- Data Sheet
- Sample code + nice code explain (โคตรยาว)
- Some explanation how it work but use difference function.
- http://www.intmath.com/trigonometric-graphs/music.php
- http://narodstream.ru/stm-urok-48-usb-device-audio/#codelink
###TO DO 1. I2S_AUDIOFREQ_32K -> Sample frequency 16K - Sample-rate: 48 KHz - Channel-size: 16 bit - Channel(s): 2 (stereo) - STM provides MCK ```c static PDMFilter_InitStruct pdm_filter;
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_CRC, ENABLE); pdm_filter.LP_HZ=8000; pdm_filter.HP_HZ=10; pdm_filter.Fs=FS; pdm_filter.Out_MicChannels=1; pdm_filter.In_MicChannels=1; PDM_Filter_Init(&pdm_filter);
PS. just work only CS43L22 without using UART.