Participle I of transitive verbs has special forms to denote the active and the passive voice.
When writing letters he does not like to be disturbed.
Being written in pencil the letter was difficult to make out.
Having written some letters he went to post them.
Having been written long ago the manuscript was illegible.
Participle II of transitive verbs has a passive meaning, e, g. a broken glass, a caged bird. Participle II of intransitive verbs has no passive meaning; it is used only in compound tense-forms and has no independent function in the sentence unless it belongs to a verb which denotes passing into a new state, e. g. a withered flower, a faded leaf