Project to extend Fastbus standard to small modules and crates

Lower-level Fastbus subsystems FG-2, FB-3, FB-4, and FG-4A on printed circuit boards of 233.35 x 280, 233.35 x 160, and 100 x 160 mm with C-96 connectors and 32, 24, and 16 A/D bits are proposed and defined. The Fastbus protocol is expanded with the introduction of subaddresses and data-byte access. All specifically standardized functions of all control and status registers are retained and placed in 16 bits. Transposition of the register bits in the segment links allows subsystems to be united in any combination during an address cycle with a single algorithm for the upper- and lower-level protocols