embeded/raspberry pi2022. 8. 17. 15:54

SPI 통신시

2MHz 클럭에 3200Hz / 1600Hz 사용 가능

 

I2C 통신시

400kHz(고속 i2c)일 경우 800 Hz

100kHz(표준 i2c) 200 Hz에

SPI
The maximum SPI clock speed is 5 MHz with 100 pF maximum loading, and the timing scheme follows clock polarity (CPOL) = 1 and clock phase (CPHA) = 1.

Use of the 3200 Hz and 1600 Hz output data rates is only recommended with SPI communication rates greater than or equal to 2 MHz. The 800 Hz output data rate is recommended only for communication speeds greater than or equal to 400 kHz, and the remaining data rates scale proportionally. For example, the minimum recommended communication speed for a 200 Hz output data rate is 100 kHz

I2C
Due to communication speed limitations, the maximum output data rate when using 400 kHz I2C is 800 Hz and scales linearly with a change in the I2C communication speed. For example, using I2C at 100 kHz would limit the maximum ODR to 200 Hz

 

4 wire는 CS / SCLK / SDI / SDO를 쓴다면

3 wire는 CS / SCLK / SDIO 로 쓰는 듯.

(SDIO Serial Data Input Output의 약자 Secure Digital I/O의 약자이기도 하니.. 주의!)

[링크 : https://www.analog.com/media/en/technical-documentation/data-sheets/ADXL345.pdf]

Posted by 구차니