I think I've tried every bit combination to 37.1.3.3.2 TRNG0 Miscellaneous Control (TRNG0_MCTL). I've followed the datasheet, I just can't get it to work. Always with unclearable errors and bad frequency counter values, even though I leave them on default values.
I turn off the PRGM bit, I turn on TRNG_ACC, sometimes together, sometimes in that order, and sometimes the reverse. I've tried setting RST_DEF or FOR_SCLK before doing that. Nothing seems to work- always unclearable errors.
I've done it in C and I've done it from the debugger, nothing works.
I would appreciate any suggestions.