Seagate BARRACUDA ST39173FC - Manual (Page 28)

26 Barracuda 9LP FC Installation Guide, Rev. A
*Short pins in mating backpanel connector.
[1] This pin may be connected to external logic to detect the presence of the drive.
The drive connects this pin to the common ground.
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/output
37 SEL_1 TTL input/output
38 SEL_0 TTL input/output
39 Reserved NC
40 5 Volts charge
Pin/contact Signal name Signal type