Stephen J. Cannell, the prolific television writer and producer who co-created "The Rockford Files" and "The A-Team" and later became a bestselling novelist, has died. He was 69.

Cannell died Thursday evening of complications associated with melanoma at his home in Pasadena, his family said.

In a career that began in the late 1960s when he sold his first TV script and took off as he soon became the hottest young writer on the Universal lot, Cannell created or co-created more than 40 TV shows, including "Baa Baa Black Sheep," "Baretta," "The Greatest American Hero" and "21 Jump Street."

Cannell, who formed his own independent production company in 1979, wrote more than 450 TV episodes and produced or executive-produced more than 1,500 episodes.

"He was one of the masters of good, old-fashioned generic television," said Robert Thompson, a professor of television and popular culture at Syracuse University and author of the 1990 book "Adventures on Prime Time: The Television Programs of Stephen J. Cannell."

"He did detective shows, he did adventure- dramas, he did fantasies," Thompson said. "He wasn't one of these guys who did, like, 'The Sopranos.' He was a meat-and-potatoes producer, writer and creator of television shows. And he did meat and potatoes really, really well."

"'The Rockford Files," the 1974-80 detective series co-created by Roy Huggins and starring James Garner, "was kind of a standard, formulaic detective genre show, but it was brilliantly executed. And Cannell could write state-of-the-art dialogue like few others of his time," Thompson said.

In 1978, he shared an Emmy Award for outstanding drama series for "The Rockford Files."

From writing "this really great dialogue" on "The Rockford Files," Thompson said, "he'd go on to form his company and do a show like 'The A Team,' this kind of goofy, fantasy Lone Ranger-like program. But once again, in Cannell's hands, it became a huge hit. It was delightfully funny to watch."

David Chase, who wrote and produced for "The Rockford Files" and later created "The Sopranos," recalled Friday that Cannell's characters displayed "weaknesses — they were fallible human beings. That was the beginning of viewers seeing a TV protagonist as someone like themselves."

Early on, Cannell developed a reputation for being extraordinarily prolific.

Indeed, in the spring of 1986, he had six hourlong shows on in primetime: "The A-Team," "Hunter," "Stingray," "Riptide," "The Last Precinct" on NBC and "Hardcastle & McCormick" on ABC.

Former NBC executive Warren Littlefield said the Cannell touch gave NBC a huge boost in the '80s.

"He understood what I'd call the vitamins and minerals of what the audience needed," Littlefield told The Times on Friday. "The daily grind of life can be so difficult for lots of people, and his shows would let you forget all that for an hour and just enjoy the thrill of the adventure."

Veteran producer Steven Bochco, who had been friends and colleagues with Cannell since the early '70s, recalled that every young writer on the Universal lot would stop by Cannell's office to read scripts from "The Rockford Files."

"They were so smart and so funny, and he was just knocking them out one after the other," Bochco told The Times on Friday. "He was not a cookie-cutter writer — he was completely original."

Saying Cannell had "boundless imagination" and was a master craftsman "who always did his homework," Bochco added: "As gifted and talented as he was, we all loved him because he was just one of the dearest people alive."

Since his first novel, "The Plan," was published in 1995, Cannell wrote 15 other novels, including the Shane Scully crime series.

Cannell's prolific output as a writer came despite having dyslexia, a reading disorder that caused him to flunk three grades before he finished high school.