------------------------------------------------------------------------------- NXP PCA9571 ------------------------------------------------------------------------------- The NXP PCA9571 chip is an 8-bits I²C output expander. Details: https://www.nxp.com/products/analog/interfaces/ic-bus/ic-general-purpose-i-o/remote-8-bit-general-purpose-outputs-for-1-mhz-i2c-bus:PCA9571 https://www.nxp.com/docs/en/data-sheet/PCA9571.pdf Logic analyzer setup -------------------- The logic analyzer used was a Hobby Components HCTEST0006 (at 2 MHz): Probe I²C signal ---------------------- 0 SDA 1 SCL Data ---- The sigrok command line used was: sigrok-cli -d fx2lafw -c samplerate=2mhz --time <time> \ --channels 'D0=SDA,D1=SCL' -o <filename.sr> This is a set of example captures of NXP PCA9571 I/O accesses. Three traces are included: - pca9571_simple.sr: a simple output write operation. - pca9571_sequence.sr: 64 consecutive write operations. - pca9571_warning.sr: this produces a warning because the first read value is different from the expected one (the PCA9571 start-up 8-bits port status is high logic level 0xFF). This may occur if the first monitored operation is a read operation and the PCA9571 is not in its default state or if the PCA9571 reboots during the monitoring.