read 4 channels values always 0

[djsg]

This code seems not working. I always get 0 readings for all 4 channels.

The read last 4 bits of STATUSCOM register is always 1111, which means 4 channels are not ready according to data sheet.

What am I missing?

[biomurph]

Are you using an OpenBCI Ganglion?

[djsg]

Yes.
For MCP3912, if we use internal clock CLKEXT = 0, the 4 read values are all 0;
if we use external clock, the readings are OK