Companion Device; Usb Flash Drive Power Controller; Usb Hub - Micros Systems Workstation 4 LX Service Manual

WS4 LX Technical Overview
USB Interface

Companion Device

U29, the CS5536 companion device supplies four USB ports. Two of these ports,
USB0 and USB3
connector. Regulator U6 provides switched +5V power to CN6 and over-current
protection for each port.
USB Flash Drive Power Control
The output of the companion device is routed to J5, the USB Flash Drive
USB1
socket. In the Windows Embedded CE 6 configuration, the USB Flash Drive is the
primary boot device and must be present. However, to provide the flexibility of
booting from alternate devices such as a CF Card or a USB thumb drive, this circuit
removes power to the USB Flash Chip through a BIOS setting.
A GPIO signal from the Super IO,
field of the Special Configuration screen of BIOS Setup.
consisting of Q11 and Q12. The default setting of 'Normal' sets
enabling the switch and providing
attached to J5.
When the Boot Test Image field is set to 'Alternate,'
the switch, cutting
powers up and USB devices are detected and enumerated, the USB Flash Drive is not
found and the unit attempts to boot from an alternate source. The alternate source
could be the Compact Flash card or an external USB thumb drive connected to the IO
Panel.

USB Hub

Downstream port
The device is fully specification compatible with the USB 2.0 specification.
USB outputs
access. Regulator U5 provides switched +5V power and over-current protection for
the pair of USB ports associated with CN5.
The third output,
controller from EloTouch Systems.
4-16
are routed to IO connector CN6, located near to the DB9 serial port
UDOC_ON
VCC5_UDOC
from the USB Flash Drive socket. As the unit
VCC5_UDOC
USB2 from the CS5536 is fed to U9, an SMSC 2503 3-port hub.
and
USBDP1 USBDP2
drives U39 a USB based 5-wire resistive touchscreen
USBDP3
is controlled by the 'Boot Test Image'
UDOC_ON
to power the USB Flash Drive
UDOC_ON
are fed to IO panel connector CN5 for external
Workstation 4 and 4 LX Field Service Guide
drives a switch
high,
UDOC_ON
goes low, turns off