Question

Computer interfacing based on series interfacing has been analyzed and comprehensively studied. Data
analysis in term of errors (variance and Standard deviation), accuracy and smoothing using computer based
statistical distribution have been learned and applications of statistical distribution (binomial, Normal and
Poisson) have demonstrated by solving problems.part of questions b, c and d based on the applications of the statistical distributions (binomial or Normal or
Poisson). analyze and solved the problem by using formulas and calculations.
(a) Reference to the serial interface RS 232 and USB studies, infer the importance and
applications of latest version of serial data interface USB.

Answer 1

RS 232 was very useful powerful flexible way of connecting computing device to peripherals.However RS 232 was intended as a short distance (a few metres max) moderately low speed (9600 bps usual, up to about 100kbps in some cases, faster in very specialist situations), one device per port (exceptions proving the rule). There were many many many control signals on the original 25 pin connector which led to an utterly vast range of non standard uses and incompatabilities. The later version reduced the connector to 9 pins with still enough control signals to allow people to utterly destandardise configurations.

Getting RS 232 working between a randomly chosen terminal device and a computer or similar may have been a matter of plug in and go, or need minutes hours or days of playing and in some cases just would not work.

RS 232 does NOT provide powering per se although many people used it to power equipment in many different ways, none of them standard. Observation of the data lines will allow data signals to be identified.

Data transfer is unidirectional on a transmit and receive line and uses asynchronous framing.

Design is for 1:1 connection with no way of multidropping in an 1:N arranagement without non-standard arrangements.

USB up to USB2 is a 4 physical wire system with two power lines and two data lines. There are no physical control lines. USB3 uses more lines and details are best left for another question and answer.Initial speed was 12 Mbps, increased to 480 Mbps with USB2 and up to 5 Gbps "Superspeed" mode with USB3.

Control and configuration is all done with software using data signals which are an utterly inseparable part of the interface. Observing the data stream with an oscilloscope will not reveal the actual data component of the system.

Data transfer is bidirectional with ownership of the "bus" being an integral part of the protocol.

Connection is almost always on a 1:1 basis physically but a number of logical devices can be accommodated on the one port. Connection of N physical devices to one upstream port is usually accomplished by use of a "hub" but this is essentially a visible manifestation of an internal 1:N arrangement which is an integral part of the design.

Please give positive response.

Thank you.