EBOX Instruction Execution Unit

The EBox is the instruction execution unit in the KLlO system. A central processor is formed when a memory interface unit (MBox), 10-11 interface unit (DTE), and PDP-11/40 processor are interfaced with the EBox. The MBox is the memory interface unit in the KLlO system to which the EBox directs its core memory requests. The PDP-1/40 is the front end processor that provides console functions and bootstrapping facilities and drives the standard PDP-11 peripherals. The DTE is the interface between the EBox and the PDP-11/40 console processor. The EBox communicates with the DTE, and hence the console processor, over a 36-bit data bus called the EBus, and uses three function lines (FOO-F02), seven controller select lines (CSOO-06), and two additional signal lines (Demand and Transfer) for arbitration and control of data transfers between the EBox and its internal and external devices. A pseudo-interface, which consists of a 23-bit address, 36-bit data, a number of request type qualifiers, and additional signals (including request and response), provides for arbitration and control of data transfers between the EBox and MBox.