I was able to enable 4 SPI as according to the Forum Post. Enabling SPI0 or SPI1 together with 3-6 doesn't work. Heres my complete /boot/config.txt
There is no ping command. The best you can do is send a legal command and see a legal response.
I suggest you monitor the SPI bus (MOSI, MISO, SCLK, CS) and check that the correct data is being sent, and if so check that a response is received on MISO.
If you use a bus speed in the 100 kHz region you can use (my) piscope to visualise the bus.
Those modes do not work on the Pi's auxiliary SPI peripheral. This was determined by experiment, I don't know if it is documented.
I have not checked to see if it is still the case for the Pi4B (but I doubt the peripheral has been altered).
See my note at http://abyz.me.uk/rpi/pigpio/cif.html#spiOpen
Warning: modes 1 and 3 do not appear to work on the ...