Hijacking this page to insert a glossary of terms / FAQ, because I don't have a strong electronic background to understand every single term out there.

There seems to be a distinction between asserting a signal and driving a signal, as seen in the MachXO2 datasheet:

The MachXO2 asserts INITN active low, and drives DONE low. When INITN and DONE are asserted low the device moves to the initialization state.

According to Electronics SO, asserting a pin is to set it to its active state, which in turn depends on whether a pin is active-high or active-low. A pin marked $$ \text{RESET} $$ is active-high and $$ \overline{\text{RESET}} $$ is active low.

A more precise definition involves making a transition from inactive to active when asserting a pin (e.g. when already active, the pin must be first set inactive then active again).

De-asserting a pin/signal can mean one of two things:

1. The pin is driven: a voltage source opposite that of its active state is connected
2. The pin is floated: the pin is disconnected and an external voltage source pulls the pin to its inactive state