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| Sequenziale logic 1) Classification of the logical circuits: The logical circuits are subdivided in combinatori and sequenziali, this last to they time can be sincroni or asynchronous which ulteriorly subdivide themselves in those to fundamental way and those to impulsive way.
2) sequenziali Circuits sincroni: They are of the circuits for which the escape is also function of the state in which they they are found which it can only change in correspondence of the impulses of a clock.
3) asynchronous sequenziali Circuits: They are systems for which the varied state with continuity, the modification of the state can be controlled from the incomes in way fundamental that is a single varied income on one be stable or in way pulse in which the varied income sul reduction or climb forehead.
4) Modality of description of the sequenziali circuits: Characteristic equation The logical function is written like if it were a combinatorio circuit considering the successive state Q like a function of the state puts into effect them q Present Table Been/Next Been In the table of classic truth beyond to the incomes Set and Reset a column with the state becomes part also puts into effect them q of the escape, according to these incomes obtains the successive state Q of the escape. Diagram of state To the inside of the circles there are the possible express states of the system is with a name that with the configuration of bit correspondent to the state, the circles are interconnected between of they through of arch on which are brought back the value of the incomes for which it is passed from one be to the other. Algorithmic Paper Been Machine One state and its attributes is brought back on the credit side inside of a rectangle, in a rumble instead is contained the regarding conditions the incomes finally in a rectangle with the edges dulls to you is contained the escapes that depend are give it be that dagli incomes. Every paper ASM is constituted from more blocks everyone of which is combinable to one be, the escapes from one be leads necessarily to an other state. Map of Karnaugh The incomes come puttinges in horizontal while the state puts into effect them in vertical, the constructed map therefore can also be diminished with the usual criteria of grouping of the 1. Map of transition Beginning from a K map in which the stable states they come emphasizes, the transition you is horizontal if the state is stable while it is vertical if the state is unstable. It is observed that the stable states are those for which Q = q. Map of flow He is equal to the transition map but hour the passage from one be to an other comes evidenced by means of an arc. Temporal diagram The temporal courses bring back themselves of mark them of income and escape from the sequenziale device on the same diagram, with of the arrows that they evidence which income determines the variation of the state of escape of the system.
5) Typology of bistable members of memory: to) Latches b) Master-Slave c) Edge-Triggered
6) Characteristic of the functions of transfer of the doors Nand and Nor: The escape of the Nor is to the high state only when both the incomes are to the low state while the escape of the Nand door is to the state low only when both the incomes are to the high state.
7) FFSR: Realization with Nor doors Two Nor doors are had of which one it has in income marks them Set and the other marks them Reset, according to income of both are taken from the escape of the other. The analysis is carried out leaving from the door that sure has the escape to 0 in how much or the Set or the Reset is high. For this configuration the incomes S=1 R=1 cannot be used in how much in the passage to the configuration S=0 R=0 the escape can be found in one be indefinite. Realization with Nand doors Two Nand doors are had of which one it has in income marks them Set and the other marks them Reset, according to income of both are taken from the escape of the other. In the symbol of this FFSR the incomes S and R are indicate to you with a bullet in how much the device work as a FFSR to having Nor the incomes denies to you, in fact are had that when S=1 the escape instead going to 1 goes to 0 while when R=1 the escape instead going to 0 goes to 1. For the same reason moreover it is had that the used configuration of income is not S=0 R=0.
8) Latch SR Gated: Draft of a FFSR in which the incomes instead of being it directly applies you to the Nor doors, is come applies you to two And that has in common an income of control C, when this is to the low state, both the incomes of the FFSR realized with Nor doors is to level 0 and therefore the escape remains memorizzata, when instead C is to the high state then the circuit is behaved like a normal school FFSR.
9) Latch D Gated: Draft of a FFSR having Gated a single income that is brought back invert to the income of reset, in this way forces the incomes to being various between of they and therefore in both the cases the Latch filler in escape the value of the income and maintains it memorizzato.
10) Latch JK Gated: It is a FFSR to doors NOR Gated through two And doors to which come also sendes the correspondents to you marks them of escape, in such a way it is succeeded to make that configuration S=J=1 R=K=1 can be used and gives place to the reversal of the escapes.
11) Latches T Gated: Draft of a having FFJK the incomes connected between of they in such a way obtains that when the T income = the 1 escape changes be while when T = 0 the escape remains in the state in which it was found previously.
12) Flip Flop Master Slavic: It is constituted from two FFSR of which the Master is Gated and the income that controls some the activation is sended to invert to the Slavic FFSR also here like income of control, the result that if of it it obtains is that only one of the two FFSR is active and therefore to the first blow of clock the incomes J and K they pass to the escapes of the first FFSR while to according to blow of clock they they become the escapes of according to FFSR.
13) Flip Flop Edge Triggered: Draft of a Flip Flop that is active and concurs to only change be to its escapes during the forehead of climb or reduction of the clock.
14) Table of general excitation for the Flip Flop Edge Triggered:
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