Input/Output Interfaces

5.6.1 USB Connector

These systems provide type-A USB ports as shown in Figure 5-7.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

1

2

3

4

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Figure 5-7. Universal Serial Bus Connector (as viewed from rear of chassis)

 

 

 

Table 5-6.

 

 

 

USB Connector Pinout

 

 

 

 

 

 

 

 

Pin

Signal

Description

 

Pin

Signal

Description

 

 

 

 

 

 

 

1

Vcc

+5 VDC

 

3

USB+

Data (plus)

 

 

 

 

 

 

 

2

USB-

Data (minus)

 

4

GND

Ground

 

 

 

 

 

 

 

5.6.2 USB Cable Data

The recommended cable length between the host and the USB device should be no longer than sixteen feet for full-channel (12 MB/s) operation, depending on cable specification (see following table).

Table 5-7.

USB Cable Length Data

Conductor Size

Resistance

Maximum Length

 

 

 

20 AWG

0.036

16.4 ft (5.00 m)

 

 

 

22 AWG

0.057

9.94 ft (3.03 m)

 

 

 

24 AWG

0.091

6.82 ft (2.08 m)

 

 

 

26 AWG

0.145

4.30 ft (1.31 m)

 

 

 

28 AWG

0.232

2.66 ft (0.81 m)

NOTE: For sub-channel (1.5 MB/s) operation and/or when using sub-standard cable shorter lengths may be allowable and/or necessary.

The shield, chassis ground, and power ground should be tied together at the host end but left unconnected at the device end to avoid ground loops.

Table 5-8.

USB Color Code

Signal

Insulation color

Signal

Insulation Color

 

 

 

 

Data +

Green

Vcc

Red

 

 

 

 

Data -

White

Ground

Black

 

 

 

 

 

5-10

www.hp.com

Technical Reference Guide