In his long, distinguished writing career Michael Frayn has dipped his quill in the inkwell for many genres. He is most famous as a playwright, creator of the intelligent but commercially triumphant farce Noises Off and probing morality play Copenhagen.

He started as a journalist for the Guardian newspaper, became a successful novelist, and a Russian translator, famed for his superb reworkings of Chekhov plays. He has won critical acclaim in each of his creative guises.

As he turns 77 this year, he is publishing his first foray into biography, My Father’s Fortune, which charts the life of his father, an easy-going, ill-starred salesman from North London.

“It was originally my children who came up with the idea of the book,” he explained. “They said they didn’t know much about their grandparents. They suggested I write something before I forgot it myself. Initially, I was reluctant to do it. It seemed rather a chore. But then, once I began, I became extremely involved in it. I found it very moving. I was very glad they set me off on this quest.”

The book chronicles his father’s impoverished beginnings in a cramped house in Holloway, providing for his mother and disabled sister as his alcoholic father squandered his meagre earnings on drink.

After he met Frayn’s mother, he found himself unexpectedly providing for her family also, while dealing with the onset of profound deafness. But then came a final, terrible blow, when his wife died suddenly of a heart attack at 41. He had more than his fair share of woes, but his son says: “I can’t recall him ever offering a breath of complaint about his life.

“He never suggested he had been dealt a tough hand. Quite the contrary. He was, mostly, a very cheerful man who enjoyed his life, despite some very painful passages in it.” Like most people, Frayn took his parents largely for granted until he began to consider their lives in such detail, years after they died. His book is an attempt to portray life as it seemed to his father. “When I began to do this book, I began to think about life as it seemed to him, from his perspective. I began to see the problems he was set in life, which I hadn’t really thought of before. I think that, on the whole, he rose to the challenges pretty well.”

His memories of his father are ‘mostly very affectionate’ but there’s no question that, in personality and interests, they were chalk and cheese. “We were so disparate in so many ways. Our relationship was quite comic in many ways.

“He was very quick-witted and he found me very slow-witted. Maybe I have struggled in life to overcome that perception. I’m still very slow-witted by his standards. I could never have done what he did. He was a salesman and he became deaf in later life and carried on as a salesman. How he carried on, I don’t know.”

Most people will doubt Frayn’s assertion that he’s a dullard, although he adamantly insists this to be the case. A Cambridge philosophy graduate, Frayn has always had a philosophical bent to his writing, raising ideas about identity and personhood in his novels and plays.

The theme of memory, or false memory, has occupied him before, but never has he had to confront the issue head-on. “If you think about your own memories, you realise that it’s extremely difficult to differentiate between the actual memories and memories of telling the story previously. It is absolutely impossible to work out what one is inventing and one is remembering.”

One recent activity that kept Frayn on his mettle was being appointed Cameron Mackintosh Visiting Professor of Contemporary Theatre, based at St Catherine’s College, last year. He gave three lectures and says: “The audiences were extremely quick in Oxford, as you might expect.” Some cynics suggested at the time of his appointment that the post amounted to little more than an advertisement for West End impresario Mackintosh. Frayn, however, laughs off the criticism: “I don’t think at any point I talked about Cameron Mackintosh or did PR for him directly.”

l My Father’s Fortune is published by Faber at £16.99. Michael Frayn will appear at the Woodstock Literary Festival on September 18. For full festival programme, see www.woodstockliteraryfestival.com, box office 01865 305305.