The following definitions will apply throughout this document.
LAT Internal Communications System
LAT System Initialization
Spacecraft Interface Board
PCI LAT Communications Board
Single Board Computer, generically referring to either a Director SBC or a Actor SBC (see below).
Used as a synonym for master SBC, but avoiding all the other meanings of the word master. Think Stanley Kubrick and "2001: A Space Odyssey". See definition of Actor SBC.
Used as a synonym for slave SBC, but avoiding all the other meanings of the word slave. Think "Kevin Spacey". See definition of Director.