Fastbus display module for segment diagnosis

Diagnostic test and verification tools are required to run and develop Fastbus networks. In particular, on-line program developments demand standard target modules and visual feedback of the actual bus status from a Fastbus segment during specific cycles. The two basic hardware units to provide this are a standard Fastbus slave and a cycle-latching logic which can be connected to a direct back-plane status display. The diagnostic applications are therefore threefold: the separate use of the test slave or of the latch logic, or a combined use of both of them. The combined use allows the verification of test slave cycles through the latch circuitry, revealing the corresponding bus pattern for all Fastbus signals. The Fastbus display module (FDM) developed at CERN integrates both the Fastbus slave and the latch and display logic on one card. FDM-specific test software is being developed.