I have a zero W powered via USB from a laptop. I have setup up for the SPI drivers and run a very simple test program which is:
import spidev import time spi = spidev.SpiDev() spi.open(0, 0) spi.max_speed_hz = 500000 spi.mode = 0 try: while True: resp = spi.xfer2([0xAA]) time.sleep(0.1) except KeyboardInterrupt: spi.close()
I get the correct output but the waveforms are so noisy. Figure 1
The yellow is the SCLK pin and the red is the MOSI outputting one byte of 0xAA
The voltages are between 0 and 3.3. I looked at this because I can not receive data by the slave, but there could be a hundred reasons for that. What I would like to know, is this noise level normal and could it affect the slave device.