I issued a SndCmd and RcvCmd sequence (see gDrvSpi8301Vars); this updated Stat_Reg_1.
The FAULT element in this status structure was updated with 1024 and the GVDD_UV element was updated with 512.
The GVDD_UV element indicates a GVDD undervoltage. I don't know why this condition is occurring; maybe the DRV8301 is no longer functioning as it should.