Seagate ST34501FC manual SEL2

26	Cheetah 4LP FC Installation Guide, Rev. B
Pin/contact	Signal name	Signal type
26	Ground
27*	+Port B_in	Diff. PECL input pair
28*	–Port B_in
29	Ground
30*	+Port A_out	Diff. PECL output pair
31*	–Port A_out
32	Ground
33*	+Port B_out	Diff. PECL output pair
34*	–Port B_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