Microprocessor hardware and software is usually commissioned with the aid of a dedicated support tool, be it a “universal” or manufacturer-specific development system. The paper outlines a different support facility for microprocessors based on a general-purpose host and a star network of microprocessor satellites. The host-satellite configuration is described, together with a suitable structure for the satellites. Two levels of host-satellite interaction are then discussed: one facilitates the software development cycle only, while the second adds extensive run-time support by allowing each satellite access to host file systems and other resources. Finally we describe the generation of software tools such as cross-assemblers and cross-compilers, using examples from an existing system with a PDP-1 I/Unix host