A VME based MAP node running under OS9 operating system

A description is given of a MAP-(Manufacturing-Automation-Protocol-) based LAN (local area network) node implemented in VME. It provides a high-speed communication channel for distributed-intelligence systems. The node has a 20-MHz, 32-bit processor, which executes the software layers of the OSI (Open Systems Interconnection) communications model, and a LAN coprocessor, which carries out the lowest level of the OSI functions, including physical and medium-access-control layers. The node includes 512 Kbytes of dual-ported RAM for use as a shared resource on VME, to support block transfers. A real-time multitasking operating system supports all VME and MAP software, allowing multiple communication processes and optimization of local resources.<
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