Using the phonetic representation (IPA), you can obtain a writing system similar to the pinyin.
Hanyu Pinyin Hànyǔ Pīnyīn Fāng'àn
Bopomofo ㄏㄢˋ ㄩˇ ㄆㄧㄣ ㄧㄣ ㄈㄤ ㄢˋ
IPA [xân.ỳ pʰín.ín fáŋ.ân]
Cameroonian dialect are written using the GACL who is similar to the IPA.
Clafrica: Pookai2t peu2nze2e2 n*kut !
Shʉ̄pāpə̀m (Bamoun): Pookɛ́t pә́nzéé ŋkut !