D3 Library and SDK
At the heart of the
flexibility of C_wiz is the D3 (data device driver)
What is a D3
There are an enormous
range of potential devices that could supply data on a
vessel. To cope with this challenge C_wiz has been
specifically designed to be independent of all data
C_wiz itself has no
knowledge of the characteristics or behavior of any data
device that may be supplying data. This is handled by
data device drivers - small pieces of software,
independent of C_wiz, that may be written by third
feature of C_wiz allows it to be interfaced to
almost any source of data in an extremely flexible
This concept is very
similar to that used by Microsoft Windows to interface
to the galaxy of printers that are available - every
printer comes supplied with a printer driver.
Most data that C_wiz is
normally required to acquire exists in the real world as
some physical condition of some physical entity. By
nature, it is "analog" or continuous with respect to
C_wiz, however, runs on a
PC which is a "digital" device, a wholly artificial
world of 0's and 1's in which data can only be kept in
the form of samplings at points in time.
For the data to pass from
the analog world to the digital, various combinations
of hardware and software are required which we will
attempt to explain by example.
For the sake of
illustration, lets follow one possible mechanism for the
transmission to C_wiz of the pressure of an engine's
The oil pressure is measured by an oil pressure sensor
which in this case consists of a diaphragm that deflects
under pressure which in turn changes a variable
The sensor is connected via 2 wires to an analog
/digital converter, in this case a VDO Logic Combi,
which takes the variable resistance reading and, once
every second, converts it to a digital message.
The VDO Logic Combi is connected via an RS232 cable to a
COM port on the PC running C_wiz, which is also running
a small piece of purpose written software (in this case
named VDO Logic Combi.d3x) which reads the digital
message, once every second, and converts it into a form
understood by C_wiz.
The small piece of purpose written software sends an
intra-PC message containing the converted digital
message to C_wiz via the Microsoft Window's internal
In C_wiz parlance:
The engine is a "data source".
The engine's oil pressure is a "data parameter".
The VDO Logic Combi is a "data device".
The small piece of purpose written code running on the
PC is a real "data device driver".
The intra-PC message is a "data device driver message".
Current D3 Library
Software Development Kit (SDK)