His invention brought digital technology to a new breed of consumer devices and powered early Apple and Commodore computers.

Credit...Tom Munnecke/Getty Images

Chuck Peddle, the engineer and entrepreneur who helped launch the age of the personal computer after designing a microprocessor that sold for a mere $25, died on Dec. 15 at his home in Santa Cruz, Calif. He was 82.

His partner, Kathleen Shaeffer, said the cause was pancreatic cancer.

In 1974, Mr. Peddle and several other engineers were designing a new silicon chip at the Motorola Corporation in Phoenix when the company sent him a letter demanding that he shut the project down.

Mr. Peddle envisioned an ultra-low-cost chip that could bring digital technology to a new breed of consumer devices, from cash registers to personal computers. But his bosses saw it as unwanted in-house competition for the $300 processor Motorola had unveiled that year.

So Mr. Peddle moved the project to MOS Technology, a rival chip maker near Valley Forge, Pa., taking seven other Motorola engineers with him. There they built a processor called the 6502. Priced at $25 — the cost of a dinner for four, and the equivalent of about $130 today — this chip soon powered the first big wave of personal computers in both the United States and Britain, including the Apple II and the Commodore PET.

“The market needed a cheap one,” Mr. Peddle said in a 2014 interview with the Computer History Museum.

In later years Intel, the Northern California chip giant, would come to dominate the personal computer business. But the market was seeded in Valley Forge, not Silicon Valley.

“Chuck Peddle is one of the great unsung heroes of the personal computer age,” said Doug Fairbairn, a director at the Computer History Museum in Mountain View, Calif. “Virtually all of the early, successful, mass-market personal computers were built around the 6502, not chips from Intel or anyone else.”

Charles Ingerham Peddle was born on Nov. 25, 1937, in Bangor, Maine, the oldest son of Thomas and Maxine (Denno) Peddle. His father was a salesman, his mother a commercial illustrator. In high school Chuck dreamed of being a radio announcer. (Television was still in its infancy.) But after traveling to Boston for an audition, he realized that his talents lay elsewhere. At the suggestion of a neighbor, he enrolled in the engineering school at the University of Maine.

After graduation, his aim was twofold: He wanted to live in California, and he wanted to build computers. So he took a job with General Electric, where he helped design early space vehicles, electronic cash registers and so-called time-share computers, massive mainframes that could be shared across companies, schools and other organizations.

Later, at Motorola, he worked on the 6800 chip, a $300 processor used in pinball machines and other arcade games, before turning his attention to a lower-cost processor. When the company sent him a letter killing the project, he responded with a letter of his own. He told Motorola that because it was abandoning the project, all the work he had done now belonged to him.

When he first took the idea to MOS Technology, one of the company’s founders, L.J. Sevin, turned him down, worried that Motorola would sue. So Mr. Peddle took the project to the other founder, John Paivinen, with whom he had worked at General Electric. Mr. Paivinen gave his approval.

After Mr. Paivinen had brought Mr. Peddle and the other Motorola engineers to Valley Forge and they built their low-cost chip, Motorola sued, just as Mr. Sevin had predicted. MOS fought the suit for years before paying a $200,000 fine.

By then, its $25 chip was feeding the rise of the personal computer. At MOS, Mr. Peddle built a personal computer around his new chip called the KIM-1 (the letters stood for Keyboard Input Monitor), and he started selling chips to a pair of young entrepreneurs, Steve Jobs and Steve Wozniak, who were building a company called Apple.

In 1976, MOS was acquired by a calculator company, Commodore Business Machines, and Mr. Peddle became its chief engineer. Soon after, Mr. Jobs and Mr. Wozniak offered to sell Apple to Commodore, but Commodore declined. Mr. Peddle and his new company built their own personal computer around the 6502: the Commodore PET, which sold for $495.

“That’s when the personal computer market really took off,” Bill Seiler, who worked alongside Mr. Peddle on the first Commodore computer, said in a phone interview.

The 6502 also powered the Atari gaming console, which brought video games into the home, and the BBC Micro, which introduced personal computers to Britain.

In the early 1980s, Mr. Peddle founded another PC company, Sirius Systems Technology, where he designed a machine called the Victor. In later years he built NNA Corporation, which made a computer with removable hard drives, letting people carry data from place to place — a forerunner of the USB stick.

In addition to Ms. Shaeffer, Mr. Peddle is survived by three brothers, Douglass, Duncan and Shelton Peddle; a sister, Marthalie Furber-Peddle; three sons, Thomas and Robert Peddle and Vernon Prestia; three daughters, Debbie and Diane Peddle and Cheryl Prestia; seven grandchildren; and five great-grandchildren. His two marriages ended in divorce.

The PC age is now on the wane, but Mr. Peddle’s big idea is just getting started. “His big thing was distributed intelligence, putting microprocessors in everything,” Mr. Seiler said. “And nowadays, microprocessors are going into everything.”