In 1980, Apple reorganized, splitting off a new "Disk Division" headed by John Vennard, responsible for developing a hard disk code-named "Pippin" and a next-generation floppy disk code-named "Twiggy." Both were intended for the Lisa project and eventually across Apple's entire product line. At Rod Holt's request, I wrote early diagnostics for Twiggy using an Apple II, but I felt lucky they asked Rich Williams instead of me to join the Disk Division as their software lead, as focusing solely on disks seemed limiting.
Woz's Apple II floppy disk design was ahead of the industry, so Apple felt confident in its ability to innovate and extend its lead. Twiggy was ambitious, quadrupling standard floppy capacity by doubling the data rate (requiring higher-density media) and using innovations like motor speed control, which slowed disk rotation on outer tracks to store more data.
The Lisa was designed with two built-in Twiggy drives, making it logical for the Macintosh to use Twiggy as well. However, Twiggy's Woz-style controller required precise microprocessor timing and couldn't tolerate interrupts—acceptable for the Apple II but not for the Lisa. The Lisa hardware team (Paul Baker, Bob Paratore, and others) solved this by embedding a faster Apple II with dedicated memory and microprocessor to control the drives.
Lisa also supported an optional external hard drive via a built-in parallel port. As Twiggy faced unexpected error-rate issues, Lisa increasingly relied on the hard drive. Twiggy was slower than expected due to high error rates and increased seek times from variable motor speeds. Additionally, Lisa's OS designers relied on disk-based memory swapping, impractical at floppy speeds. Soon, the hard drive became mandatory, increasing Lisa's minimum price by over $1,000.
Lisa launched with fanfare in January 1983 but wasn't ready to ship. Production was hampered by Twiggy's low yield and high error rates. Units shipped in June 1983, but drive issues persisted.
Meanwhile, the Mac team panicked. We used a single Twiggy drive without a hard drive fallback. Twiggy seemed unreliable and too costly for Macintosh, but we had no alternative. Without a quick replacement, the project would face indefinite delays.
Fortunately, we learned of Sony's new 3.5-inch drive, launched in spring 1983 via HP, their partner. George Crow, Mac's analog engineer (formerly at HP), championed Sony's superior drive. He procured one from HP and proposed interfacing it with the Mac while negotiating with Sony.
The Sony drive was impressive compared to Twiggy: same data rate, smaller disks (shirt-pocket size), and a durable plastic shell. Steve Jobs, ready to abandon Twiggy, loved the Sony drive and wanted to adopt it. Instead of partnering with Sony, he insisted Apple engineer its own 3.5-inch drive with Japanese partner Alps Electronics, which manufactured Apple II drives cheaply.
George Crow and Bob Belleville saw this as suicidal. The Mac was seven months from launch, and replicating the drive in time seemed impossible given the Disk Division's track record. But Steve insisted, ordering work on Sony's drive to stop. He sent Rod Holt, Bob, and George to Japan to launch a crash project with Alps.
Bob and George reluctantly agreed but secretly continued working with Sony. Larry Kenyon was tasked with interfacing a Sony drive—in secret. They also arranged Sony meetings to discuss customizations and a potential deal.
This dual-track approach involved frequent, secret meetings with Sony. When Sony engineer Hide Kamoto visited Cupertino to work with Larry, Steve Jobs unexpectedly entered the area. George, fearing questions, quickly told Kamoto to hide in a nearby janitorial closet. He stayed there for five minutes until Steve left.
Later, George and Larry apologized. "No problem," Kamoto said. "But American business practices—they are very strange. Very strange."
As predicted, Alps estimated 18 months for production, forcing us to abandon the project. When Bob revealed the ongoing Sony efforts, Steve admitted they'd done the right thing. The Sony drives succeeded, and it's hard to imagine Mac without them.