Specifications

Chapter 1 - Introduction to Microprocessors
As we have separate lines for receiving and sending, it is possible to receive and send data
(info.) at the same time. So called full-duplex mode block which enables this way of
communication is called a serial communication block. Unlike the parallel transmission, data
moves here bit by bit, or in a series of bits what defines the term serial communication comes
from. After the reception of data we need to read it from the receiving location and store it in
memory as opposed to sending where the process is reversed. Data goes from memory through
the bus to the sending location, and then to the receiving unit according to the protocol.
1.6 Timer unit
Since we have the serial communication explained, we can receive, send and process data.
However, in order to utilize it in industry we need a few additionally blocks. One of those is the
timer block which is significant to us because it can give us information about time, duration,
protocol etc. The basic unit of the timer is a free-run counter which is in fact a register whose
numeric value increments by one in even intervals, so that by taking its value during periods T1
and T2 and on the basis of their difference we can determine how much time has elapsed. This
is a very important part of the microcontroller whose understnding requires most of our time.
1.7 Watchdog
One more thing is requiring our attention is a flawless functioning of the microcontroller
during its run-time. Suppose that as a result of some interference (which often does occur in
industry) our microcontroller stops executing the program, or worse, it starts working
incorrectly.
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