dp_volt_reading_t
dp_volt_reading_t reading; /* value in mV. */
dp_volt_reading_t low_warning;
dp_volt_reading_t low_soft_shutdown;
dp_volt_reading_t low_hard_shutdown;
dp_volt_reading_t high_warning;
dp_volt_reading_t high_soft_shutdown;
dp_volt_reading_t high_hard_shutdown;