Seagate ST19171FC manual Pin/contact, Signal name, Signal type

22		Barracuda 9FC Installation Guide, Rev. A
	Pin/contact	Signal name	Signal type
	26	Ground
27*		+CH2_in	Diff. PECL input pair
	28*	–CH2_in
29		Ground
	30*	+CH1_out	Diff. PECL output pair
31*		–CH1_out
	32	Ground
33*		+CH2_out	Diff. PECL output pair
	34*	–CH2_out
35		Ground
	36	SEL_2	TTL input
37		SEL_1	TTL input
	38	SEL_0	TTL input
39		Reserved NC
	40	5 Volts charge

*Short pins in the mating backpanel connector.