## Guide For Students

Cyclic codes are among block systematic codes in which each combination is coded independently (in a look the block in such a way that information k and control m symbols always are on certain places.

For synchronous cascading the chip has two entrances of permission of SULFURS and the SET, and also the HARDWARE exit (the terminations the account. The counter considers clock impulses if on entrances the SET and SULFURS of tension of high level.

Testing of programs as "White box". Test data sets are projected on the basis of internal logic of the program. The testing purpose - to check each branch, every way and each operator. The specification of the program thus is not used.

Use of not given polynomial of P(X) which in relation to cyclic codes is called forming, by the generator or the making polynomial (polynom) is the basis for cyclic coding.

multiplication of the set code combination of G(X) by Xm monomial having the same degree, as forming P(X) polynomial with addition to this work of the rest of R(X) received after division of the work G(X) Xm into the forming P(X) polynomial.

The program has to have the standard interface satisfying to the accepted norms correctly to work at all admissible personal COMPUTERS, the text of the program has to be convenient and readable and clear to the user.

In this work one of a set of methods of coding was considered. The advantage of this method that it can find to correct packs of mistakes. Also all cyclic codes easily give in to circuit realization.

Stochastic testing is applied when it is impossible in complex challenges to touch all combinations of basic data and to check results of functioning of the program on each of them. Thus basic test data are set by a set of random variables with the corresponding distributions and for comparison of the received results also distributions of random variables are used. Stochastic testing is applied generally to detection of mistakes.

Testing of programs as "Black box". Aims clarifications of circumstances in which the behavior of programs does not meet the specification. Test data are formed and used without knowledge of internal structure of the program.

Static testing is the most formalized and automated method of verification of programs. As standards rules of structural creation of program modules and data processing are applied. An inspection of degree of these rules is carried out without use of an object code of the program by the formal analysis of the text of the program in a programming language. Operators and operands of the text of programs thus it is analyzed in a symbolical look therefore such method is called symbolical testing.

According to the specification and according to the data obtained on a term paper the forming Fayr's polynomial of P(X). According to a formula (we find L ≥ 3, from where it is possible to accept L = we choose not given P(X) polynomial From the corresponding tables =x3+x+1 = 101

According to the specification on a term paper it is necessary to construct mathematical model of the set correcting code, to find the forming code matrix, technically to realize means for its coding / decoding (at the level of the schematic diagram), to develop the multimodular program realizing the coding device on the COMPUTER.

Without testing of programs it is impossible to create correctly working program as always there are some boundary conditions outside which the program gives mistakes. Thus it is not necessary to confuse debugging of programs and testing.

In this work the code – Fayr's code will be considered pomekhozashchishchenny (or correcting). It is the cyclic code finding and correcting packages of mistakes. Features of this code will be considered further.

Any group (n, k) – the code can be written down in the form of the matrix including k linearly - independent lines on n of symbols, and, on the contrary, any set of k linearly - independent n-digit code combinations can be considered as the forming matrix of some group code. It is possible to distinguish codes at which lines of the forming matrixes are connected by an additional condition of recurrence from all variety of such codes.

Possibility of detection and correction practically of any mistakes at rather small redundancy in comparison with other codes, and also simplicity of circuit realization of the equipment of coding and decoding was made by these codes widespread.