Testing the board with a M5Stack
What is the M5Stack ?
That's an ESP32, with a screen of 320x240.
For a 120us acquisition, that leaves 3us per pixel.. Still interesting to see. Moreover, there seems to be a 512KB RAM, would be enough to store long acquisitions. One line is 256kB at 64Msps.
Even a FFT processing would be possible.
Connectors necessary were :
- M5STACK pin22 -> RPi header GPIO 23 (Ice40 reset)
- M5STACK pin21 -> RPi header GPIO 8 (Ice40 CS)
- M5STACK pin19 -> RPi header GPIO 10 (Rpi MISO)
- M5STACK pin23 -> RPi header GPIO 9 (Rpi MOSI)
- M5STACK pin18 -> RPi header GPIO 11 (Rpi CLK)
- M5STACK GND to RaspberryPi header GND pin
- M5STACK 5V -> RaspberryPi header 5V pin
Only SPI libs and M5Stack were necessary.. and a proof of concept was done with a single line acquisition process, for 200us, with a low gain.
With the calibration rig
With a piezo in a mug