System Boards And Components; Ws4 System Boards - A Short History - Micros Systems Workstation 4 LX Service Manual

System Boards and Components

This section starts with a discussion of each system board revision from the first
generation, through the first 'ROHS' compliant revision, then on to latest system
board, the WS4 LX.
In order to keep confusion to a minimum, each system board is referenced by a model
designation printed on the board.

WS4 System Boards - A Short History

The AB28-'n' designation (where 'n' represents the hardware revision), indicates the
'original' non-ROHS compliant series of WS4 System Boards. Close to 100000 units
were produced with the AB28 Series, including AB28-F, AB28-G and AB28-I.
Figure 1-2 displays the AB28-I System Board, the most numerous example of the
AB28 series, and points out the location of the model number.
Figure 1-2: The AB28 Series Workstation 4 System Board
The transition from AB28-F/G to AB28-I system boards combined with the change
from a Samsung LCD to a Sharp LCD forced changes in the LCD and backlight
cables. This is reflected in the section on replacement cables.
Another important change between the AB28-F/G, and AB28-I system boards is the
addition of a multiplexer on the COM 3 port, shared between the Mag Stripe Reader
and Customer Display port. The AB28-I System Board required updated platform
files in order for the mag stripe reader and customer display interfaces to function
properly. Chapter 2 provides more detail about the multiplexer.
Workstation 4 and 4 LX Field Service Guide
Introduction to the WS4/WS4 LX FRUs

System Boards and Components

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