Siemens A35, A36, A40, C25, C35, C45, M35, M35i, M50, ME45, MT50, S25, S35, S45, SL-42, SL45, 3118 cell phones

12 pin Siemens Lumberg cellphone special connector at the mobile phone

Pin	Name	Dir	Description
1	GND	-	Ground
2	SELF-SERVICE	in/out	Recognition/control battery charger
3	LOAD	in	Charging voltage
4	BATTERY	out	Battery (S25 only)
5	DATA OUT (TX)	out	Data sent
6	DATA IN (RX)	in	Data received
7	Z_CLK	-	Clock line for accessory bus. Use as DTR In data operation
8	Z_DATA	-	Data line for accessory bus. Use as CTS in data operation
9	MICG	-	Ground for microphone
10	MIC	in	Microphone input
11	AUD	out	Loudspeaker
12	AUDG	-	Ground for external speaker