2020-5-21-Bone vibration test completed

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2020-5-21-Bone vibration test completed [Copy link]

 

The bone vibration test is completed. In the video, the green light is on when the paper is vibrating, indicating that breeze vibration is detected. Video address: https://v.youku.com/v_show/id_XNDY4MDYyNjQwOA==.html?spm=a2hbt.13141534.0.13141534

containsmachine

Apart from anything else, the PCB design made by the OP is very beautiful.

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Points to note about driving LIS25BA :

1. The device address selection solder point I2C_A0 on the flexible board needs to be soldered. You can choose whether to connect high or ground according to your own software. I chose a point on the outside that is easy to use the soldering iron.
2. Note the sentence in Section 5.3 on page 22 of the LIS25BA data sheet : " The slave address is equal to 001100yx (TDM mode, where y = not(I2C_A0 pin)) or in case of writing or reading respectively." - In the slave address command word, x is the read/write bit; in the software, the y bit is the inverse of the hardware configuration result of the I2C_A0 pin.
3. Note the sentence below Figure 13 in Section 6.2.1 on page 23 of the LIS25BA data sheet . A delay of at least 5.5 milliseconds must be added to the software before an accurate reading can be taken.
4. After each communication is established, three sampling results must be abandoned , which means that three frames of SLOT0 to SLOT7 in each frame in Figure 7 and Figure 8 of Section 4.4 on page 17 of the data page must be abandoned , that is , the axis data words after SLOT24 (inclusive) are taken as valid words.
5. I use the I2S communication protocol to read the data.

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By the way, before sending the I2C communication command, prepare the three stable I2S clocks MCLK/BCLK/WCLK

lanhua

Pictures speak louder than words!

A little more detail would be nice!