A 553 K-transistor LISP processor chip

The authors describe a LISP microprocessor which includes over 550 K transistors, has 114 K of on-chip RAM, and runs instructions in a single 30-ns clock cycle. The chip is implemented in 1.25-/spl mu/m double-level-metal (DLM) CMOS, has 224 pins, and is packaged in a custom pin-grid array. The microinstruction and macroinstruction sets of this chip are compatible with an existing LISP processor. An extensive discussion of test features designed into the processor chip is given.