Good morning everyone,
Currently researching some special effects of moovement, I designed a system logging the data of several accelerometers in order to extract components of the acceleration. My initial prototype consists of an MCU connected to 4 MPU6050s and an SD card to log the data in real time, because of the sd card's slowness, I can't go above a data rate of 100Hz (getting the data requires 1.5ms (I am at the limits of 400kHz I2C to receive the 24 bytes of data) and logging it requires 8ms)
I want to make the next prototype, consisting of 6 or 8 different 3-axis accelerometers with a target measurement rate of 200Hz. Needles to say that directly connecting the SD card to the MCU will not do the job, logging the data into the MCU's ram doesn't seems a good option to me as I want to be able to make measurements at least 30s long, the goal is to be able to log for 10 mins without issues.
My idea was the following : the circuit uses two mcus, two srams, and an sd card reader : the main MCU reads the data from the accelerometers and logs it into the first sram chip, while the second mcu reads the data stored in the second sram and logs it into the sd card, during the time of, let's say 50-100 measurements, and then the roles of the srams are reversed.
The different arams chips, are connected to one spi bus or the other thanks to traditionnal multiplexers, wich would either connect a ram chip's pin to the main mcu, or the logging mcu.
Is my idea worth it, and will I gain time gy logging in burst instead of instant by instant, or should I look for something else, like a really beeffier sram to log everything in and afterwards, store the data into the sd card ?
A hudge thanks in advance to all those who will take time to read my question.
PS and I am sory if I made mistakes of if my text isn't easy to read, but English isn't my native language