GPIOs can be configured as outputs that are based on Boolean combinations of up to two ANDs all ORed together (Figure 7-13). Inputs to the logic blocks can include the first 8 defined GPOs, GPIs and rail-status flags. One rail status type is selectable as an input for each AND gate in a Boolean block. For a selected rail status, the status flags of all active rails can be included as inputs to the AND gate. _LATCH rail-status types stay asserted until cleared by a MFR PMBus command or by a specially configured GPI pin. The different rail-status types are shown in Table 7-5. See the UCD90xxx Sequencer and System Health Controller PMBus Command Reference for complete definitions of rail-status types. The GPO response can be configured to have a delayed assertion or deassertion. The first 8 GPOs can be chosen as Rail Sequence on/off Dependency. The logic state of the GPO instead of actual pin output is used as dependency condition.

Figure 7-13 Boolean Logic Combinations

Figure 7-14 Fusion Boolean Logic Builder

When GPO is set to POWER_GOOD, this POWER_GOOD state is based on the actual voltage measurement on the monitor pins assigned to those rails. For a rail that does not have a monitor pin, or have a monitor pin but without voltage monitoring, its POWER_GOOD state is used by sequencing purpose only, and is not be used by the GPO logic evaluation.