Usb Control; Usb Connector; Figure 5-8. Universal Serial - Compaq EN Series Technical Reference Manual

5.7.3

USB CONTROL

The USB is controlled through I/O registers as listed in table 5-20.
Table 5–20. USB Control Registers
I/O Addr. Register
00, 01h Command
02, 03h Status
04, 05h Interupt Enable
06, 07 Frame No.
08, 0B Frame List Base Address
0Ch Start of Frame Modify
10, 11h Port 1 Status/Control
12, 13h Port 2 Status/Control
5.7.4

USB CONNECTOR

The USB interface provides two identical connectors (ports A and B).
Figure 5–8. Universal Serial Bus Connector (one of two as viewed from rear of chassis)
Table 5–21. USB Connector Pinout
Pin Signal
1 Vcc
2 USB-
Table 5-20.
USB Control Registers
1 2
Table 5-21.
USB Connector Pinout
Description Pin
+5 VDC 3
Data (minus) 4
Compaq Deskpro EN Series of Personal Computers
First Edition - June 1998
Technical Reference Guide
3 4
Signal Description
USB+ Data (plus)
GND Ground
Net PC and Small Form Factor Models
5-35