Seagate 18FC manual FC-SCA pin descriptions

Barracuda 18FC Installation Guide, Rev. A				25
Table 1: FC-SCA pin descriptions
	Pin/contact	Signal name	Signal type
1*	–EN bypass port A	TTL output
	2*	12 Volts
3*		12 Volts
	4*	12 Volts
5*		–Parallel ESI
	6*	Ground[1]
7*		Active LED out	Open collector out
	8*	Reserved
9*		Start_1	TTL input
	10*	Start_2	TTL input
11*		–EN bypass port B	TTL output
	12*	SEL_6	TTL input/output
13*		SEL_5	TTL input/output
	14*	SEL_4	TTL input/output
15*		SEL_3	TTL input/output
	16*	Fault LED out	Open collector out
17*		Reserved NC
	18*	Reserved NC
19*		5 Volts
	20*	5 Volts
21		12 Volts charge
	22	Ground
23		Ground
	24*	+Port A_in	Diff. PECL input pair
25*		–Port A_in