Micros Systems Workstation 4 Setup Manual page 97

Poly Switch
Like a traditional fuse, a Poly switch fuse limits the amount of current
flowing through a circuit to prevent damage should a fault condition
occur. Unlike traditional fuses however, when the over-current fault is
removed, the poly switch automatically resets and does not have to be
physically removed from the board and replaced.
The WS4 system board uses poly switches on the PS/2
Mouse/Keyboard, remote customer display, backlight inverter, cash
drawer outputs, and USB ports.
POST
Abbreviation for Power On Self Test. In the Workstation 4, the POST is
built into the Boot Loader, which executes each time the workstation is
powered up. It checks for the presence of the Disk On Chip and
Compact Flash Card, checks several key hardware circuits. If these
devices are missing or defective, the POST flashes the Operator LED
and sounds the beeper in a predefined fashion to report the error.
Registry
The registry is a database that acts as a central repository for all
hardware and software configuration information for the Windows
operating system and applications.
When Windows CE is running, the registry is located in RAM where it
can be quickly accessed. When the OS or application examines,
modifies, or creates a registry entry, it occurs in the RAM version,
called the Working registry.
A driver called the Persistant Registry Driver (PRD) periodically copies
the working registry in RAM to the Compact Flash card where it
becomes the Persistant registry. This protects the registry contained in
RAM, which will be lost if AC power fails. If AC power is lost, the PRD
restores the persistant registry on the CF to RAM when the OS boots.
Because the CF card contains in addition to an up-to-date copy of the
system registry, the POS application and optionally SAR data, it
represents the personality of the workstation. This forms the basis of a
WS4 'personality swap.'
Registry Editor
An editor that can modify the contents of the Working registry directly,
but is only used for technical reasons or as a last resort. Registry
settings are typically modified only by application installation
programs, or by changing settings in the Windows Control Panel.
Workstation 4 Setup Guide
WS4 Glossary
Glossary-7