Other: IT
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TMS
Computer Architecture Cont.
An example of a single element that works
as both primary and secondary would be a piezoelectric crystal which itself converts mechanical strain to an electronic signal through the
unique properties of piezoelectric crystals. The
signals, especially biosignals, are small in amplitude and susceptible to errors. A signal conditioner is used to compensate for theses inherent errors. At this stage a properly conditioned
signal can be created on an analog display and
seen by a user. With the move to digital circuits,
digital displays, and digital signal processing,
(dsp’s being special microprocessors used for
high computational signal processing) medical
devices have evolved more into computing devices. What makes the medical device into a
microcomputer? Its easier to visualize now that
some medical devices are utilizing keyboards, a
mouse, and touch screen monitors.
Fig 4. ECG machine. The main processor is on the main board.
Even though a medical device does not resemble a computer on the outside; it’s what is
on the inside that matters. The photos below
show two different computing devices. Both of
these devices can be considered early models,
maybe even classic. The fig 4 shows the open
case of an ECG machine, fig 5 shows the inside
of a computer. In the next article we will take a
deeper look at some components found in a microcomputer starting with the microprocessor.
For now, we will just refresh your memory on
microprocessor architecture. An older architecture, known as the Von Neumann Architecture
for microprocessors utilizes four key components; 1. ALU- arithmetic Logic Unit, 2. Control
Unit, 3. Memory. And 4 I/O mechanisms. In this
architecture, a stored program instruction, can
be read but not executed at the same time.
This is known as the Von Neumann bottleneck. Another architecture you may have heard
is the Harvard or modified Harvard architecture,
because true architecture, and true Von NeuFig 5. Shows the inside of a computer tower.
mann.
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