Lisp Machines - Decline

Decline

Lisp Machines, Inc. sold its first LISP machines, designed at MIT, as the LMI-CADR. After a series of internal battles, Symbolics began selling the CADR from the MIT Lab as the LM-2. Symbolics had been hindered by Noftsker's promise to give Greenblatt a year's head start, and by severe delays in procuring venture capital. Symbolics still had the major advantage that while 3 or 4 of the AI Lab hackers had gone to work for Greenblatt, a solid 14 other hackers had signed onto Symbolics. There were two AI Lab people who did not get hired by either: Richard Stallman and Marvin Minsky.

Symbolics ended up producing around 100 LM-2s, each of which sold for $70,000. Both companies developed second-generation products based on the CADR: the Symbolics 3600 and the LMI-LAMBDA (of which LMI managed to sell around 200). The 3600, which shipped a year late, expanded on the CADR by widening the machine word to 36-bits, expanding the address space to 28-bits, and adding hardware to accelerate certain common functions that were implemented in microcode on the CADR. The LMI-LAMBDA, which came out a year after the 3600, in 1983, was mostly upward compatible with the CADR (source CADR microcode fragments could be reassembled), but there were improvements in instruction fetch and other hardware differences including use of a multiplier chip and a faster logic family and cache memory. The LAMBDA featured use of the NuBus, which had been originated by Steve Ward's group at MIT, and, through a separate chain of events, was being developed by Western Digital Corporation. This allowed the popular LAMBDA "2x2" configuration whereby two machines shared one infrastructure, with considerable savings. Texas Instruments (TI) later joined the fray when it licensed the LMI-LAMBDA design and purchased the NUBUS associated assets from Western Digital and still later produced its own variant, the TI Explorer.

Symbolics continued to develop the 3600 family and its operating system, Genera, and produced the Ivory, a VLSI chip implementation of the Symbolics architecture. Texas Instruments shrunk the Explorer into silicon as the MicroExplorer. LMI abandoned the CADR architecture and developed its own K-Machine, but LMI went bankrupt in 1987 before the machine could be brought to market.