Turkey's former army chief Ilker Basbug, the highest-ranking defendant convicted in a mass trial over an alleged coup plot, has fiercely criticised his comrades for showing a lack of loyalty and support.

In his book "Suclamalara Karsi Gercekler" (Accusations Against Truth), Basbug gives an account of his two years in detention, as well as his frustration after he was jailed for life in August last year convicted of plotting to overthrow the government.

"Leading and running a terrorist organisation! Let me be clear, my world turned black after I heard the charges," he wrote.

The 71-year-old decorated general accuses the judiciary of an unfair decision, and lashes out at politicians for acting as mere bystanders, and the media for hesitating to seek the truth.

But his major disappointment was the lack of solidarity from an institution he had served for 48 years before retiring in August 2010.

"The Turkish Armed Forces, with its active and retired officers, failed by showing disloyalty to their comrades," he wrote.

Basbug, who led the army from 2008 to 2010, was the most senior officer in a crowded dock convicted of involvement in a shadowy group dubbed "Ergenekon", accused of instigating an armed uprising against Prime Minister Recep Tayyip Erdogan's Islamic-leaning government, which came to power in 2002.

Turkey's once powerful military, which considers itself the guardian of the modern and secular republic founded by Mustafa Kemal Ataturk in 1923, violently overthrew three governments in 1960, 1971 and 1980, as well as forcing out an Islamist government in 1997.

The former top commander led Turkey's military campaign against the rebel Kurdistan Workers' Party (PKK) for many years, only to be accused in retirement of having headed a terrorist group himself.

Basbug has vehemently denied the charges.

"I had never been a coup plotter, neither while I was a lieutenant, nor a chief of general staff," he wrote in the book.

Basbug, who is incarcerated in a high-security prison complex near Istanbul, said life in prison was hard.

"But the feelings and thoughts that keep everyone alive is that there is a major injustice and this injustice will one day be over."

Basbug had previously penned three books, one on terrorism and two on Ataturk. The latest book goes on sale from Monday.