Applicants whose native language is other than German have to attest their language skills according to the following regulations for Universities of Applied Sciences in the county of Baden-Württemberg.: either a successful "Test Deutsch als Fremdsprache": TestDaF [Level 4 in all 4 areas = TDN 4], or a DSH-Diploma: "Deutsche Sprachprüfung für den Hochschulzugang" [Level DSH-2].
For more information on this issue go to the website: www.sprachnachweis.de. There you also find a query which can help you with specific questions; also consider their detailed descriptions of the examinations as well as the important documents posted there.
According to the federal regulations, the University of Applied Sciences holds the right to determine variant language requirements for special purposes of studies, i.e. DSH-1 or TDN-3 in one or more of the disciplines of the tests. (§ 3 Abs. 5 / § 4 Abs. 7 der Rahmenordnung über Deutsche Sprachprüfungen für das Studium an deutschen Hochschulen / RO-DT).