Bell Labs’ Bellmac-32 paved the way for today’s smartphone chips Willie D. Jones22 May 20256 min read Willie Jones covers transportation for IEEE Spectrum and the history of technology for The Institute.

The architecture group led by Condry, an IEEE Life Fellow who would later become Intel’s CTO, focused on building a system that would natively support the Unix operating system and the C programming language. Both were in their infancy but destined for dominance. To cope with the era’s memory limitations—kilobytes were precious—they introduced a complex instruction set that required fewer steps to carry out and could be executed in a single clock cycle.

The engineers also built the chip to support the VersaModule Eurocard (VME) parallel bus, enabling distributed computing so several nodes could handle data processing in parallel. Making the chip VME-enabled also allowed it to be used for real-time control.

The group wrote its own version of Unix, with real-time capabilities to ensure that the new chip design was compatible with industrial automation and similar applications. The Bell Labs engineers also invented domino logic, which ramped up processing speed by reducing delays in complex logic gates.

Additional testing and verification techniques were developed and introduced via the Bellmac-32 Module, a sophisticated multi-chipset verification and testing project led by Huang that allowed the complex chip fabrication to have zero or near-zero errors. This was the first of its kind in VLSI testing. The Bell Labs engineers’ systematic plan for double- and triple-checking their colleagues’ work ultimately made the total design of the multiple chipset family work together seamlessly as a complete microcomputer system.

Then came the hardest part: actually building the chip.