SLVUAW9C September 2016 – February 2020 UCD90320
The margining level (low or high) can be selected with the Input Pin identified by this byte (see Table 66). The pin is ignored if the value of this byte is 0.
When this pin is asserted and the MRG_EN pin is asserted, all rails with margining enabled (see Section 10.35) are put in the low margined state.
When this pin is not asserted and the MRG_EN pin is asserted, all rails with margining enabled are put in the high margined state.