SU385298A1 - FUNCTIONAL GENERATOR - Google Patents

Description

one

The device, related to computing, can be used to generate continuous functions of an arbitrary type when specifying an argument with a unitary code. The result is in analog form.

A function generator is known that contains a read-only memory, three digital-to-analog converters, inepBoro and the second outputs of which are connected to the analog inputs of the third, two registers, the input of the first of which is connected to the first output of the permanent memory, and the output to the first a digital-to-analog converter and a second register input, the output of which is connected to a second digital-to-analog converter, a pulse generator and a meter connected in series, output connected to tert his digital-analog converter; two successively connected delay lines, the first input of which is connected to the counter overflow output and the second register setting zero, the output to the first register zero input, and the second delay line output connected to the read-only memory input.

The purpose of the invention is to simplify the device and eliminate the ambiguity of the functions developed by it. This is achieved by the fact that

the proposed generator, the output of the second register is connected to the main address input of the permanent storage device, the second output of which is connected to the counting input of the additional input counter, the output of which is connected to the additional address input of the permanent storage device.

FIG. 1 is a block diagram of a functional oscillator; in fig. 2 - functional diagram of the counter and digital-to-analog converter; “And FIG. 3 plot of the plot of the function with ordinates

... f (Xi-i) Ui- :: f (x,) U ,;

15 f (xi, i) LJt, i; ...

Functional generator contains registers /, 2, digital-to-analog converter: And

3-5, counters 6, 7, read only memory (ROM) 8, pulse generator 9, delay lines 10, 11; 12 - output ROM 8; 13, 14 - analog inputs of the digital-to-analog converter 5; 15 - output terminal

devices.

Counter 6 (FIG. 2) is made on triggers 16-18, and digital-to-analog converter 5 is on keys 19-21 and an attenuator consisting of resistors 22-27. The connections between the triggers 16-18 are not shown for simplicity. In the initial state, register ffxoj of the first ordinate is set in register 2, and f (x) of the second ordinate of the boundaries of the first approximation area of the generated function 1 (x) is set in the f register, and counter 6 is set to the zero state. The voltage from the output of the digital-to-analog converter 4, proportional to and the voltage from the output of the digital-to-analog converter 3, proportional to 1 (k-), receives respectively Hia inputs 14 and 13 of the digital-to-analog converter 5. The converter 5 operates as follows. If inputs 13 and 14 supply voltages Ui and Vi-i proportional to the codes of the t-th and ((-1) -th ordinates of the generated function (i, 2, ...) available in registers / and 2, and counter 6 is set to zero (/ 0), triggers 16–18 N are in zero state, and keys 19–21 connect all attenuator to input 14. Output voltage is 15 t / Bbrx. If in meter 6, all the triggers are set to one, which corresponds to Imax, the keys switch the attenuator links to input 13, and the output voltage 15, i) -J + Ui-i. output (, г).,. Ui - U,, Ш (1-1,1) low-order digit-analog converter 5 on the interval (/ -1.0 of the generated function. Thus. -1.0 - „- Jmax + i-l Considering that / m. T, formula (2) can be represented as Ut-Ui, (2 "-1) +. (3) BHX (, i) For any other values of the number / that are in counter 6 (i.e. O), the output voltage is determined by the more general formula oh,.:, -) + -1- (4) It should be noted that in formulas (/ -4) addition and subtraction taking into account signs, i.e., the stresses Ui and f / ii can have both positive and negative polarities, and can also be p Came zero. Thus, on the segment (il, i), there is a stepwise linear approximation of the generated function with a discreteness determined by the width of the counter 6. According to formula (4) at / 0, the output voltage 15 as the counter 6 is filled from generator 9 to jmax the voltage at output 15 changes to BbiX (Ol) 1 - D (0.1). The overflow pulse from counter 6 when imax sets register 2 to zero, and after the time determined by delay line 10, register 1 is set to zero. In this case, the code f (xT,) from the outputs of the register / is transmitted to register 2. Next, the device m Jette work differently. There may be two cases. 1. There are no identical values of the generated function corresponding to the boundaries of each approximation segment (i.e. f (x,) f (x,) H --.- + f (xi). 2. Among the values of the generated function corresponding to the boundaries approximation plots, there are the same (i.e., for example, f (-) - / (-.); f (xj f (x, ni) in the first case, after entering into register 2 the code f (xi), after the delay line // from its output to the input of ROM 8 receives a polling pulse and from the outputs of the ROM the code f (x2) of the next ordinate of the boundary value of the generated function is entered into the register / register. This is the voltage t / i. The operation of the device in the first section of the approximation was considered above. In the second and subsequent sections of the approximation, the device works similarly. At the output of / 5, a functional voltage is generated corresponding to the set values of the function at the boundaries of the sections of approximation with steps -linear approximation between them. In this case, the code value of the subsequent ordinate of the boundary of the approximation area, generated by ROM 8, is determined by the code of the previous ordinate of the approximation area boundary roxations stored at the time of polling ROM 8 in register 2: f (xi) (), g 0,1,2 ... This allowed the proposed generator to use the register of digital-analog converter as the address register of ROM, which greatly simplified the circuit . As follows from the description, if functions are generated with different ordinates of code corresponding to the boundaries of the approximation sections, counter 7 is unnecessary, which further simplifies the device. If among the values of the generated function corresponding to the boundaries of approximation sections, we find the same for concrete reasoning, we take f (,) f (,), f (xj f (x, i}), consider the operation of the device from the moment in counters 6 and 7 mc zeros, register /

is set to zero, and in register 2 there is a code

/ s.

When a polling pulse 11 arrives at the input of the ROM 8 from the output of the delay line 11 simultaneously with the code l (xk +) received from the outputs of the ROM 8 to register 1, from output 12 to the summing input of counter 7, a pulse is applied which fixes to the last unit. Further operation of the device is similar to that described for the first case up to the value f (xm) - Raznip only in that the ordinate code f (xi, +}) and the codes of the subsequent ordinates to the ordinate f (Xm) inclusive are compiled into ROM in the counter 7.

When the code in register 2, corresponding to f (xm), with the receipt "and the input of the ROM 8 from the output of the delay line 11 of the next interrogation pulse, the ROM 8 generates the code / (Xm-ii, which enters the register 1, and the impulse, which from the output 12 enters in the counter 7. The number two is recorded in the counter /.The subsequent orders of the generated function, corresponding to the boundaries of the approximation segments, are encoded according to the number two in counter 7.

So, in this case, each value of the ordinate caddy of the approximation area generated by ROM 8 is determined by the code corresponding to the previous ordinate code of the approximation area boundary stored at the time of polling of the state of ROM 5 in register 2, as well as by the number jV that have the moment in the counter 7;

f (xi) Flf (x, i), N,

i.e., counter 7 eliminates ambiguity in the coding of ordinates, which may occur with the same ordinates of the boundaries of the approximation regions.

Thus, the proposed functional generator generates functions of an arbitrary form that are continuous on a given interval of variation of the argument with simultaneous stepwise linear approximation and obtaining the result in analog form.

The transition from one function to another is possible when installed in the device removable ROM 8.

Subject invention

A functional generator, containing a permanent zero-memory device, three digital-to-analog converters, the outputs of the first and second of which are connected to the auxiliary inputs of the third, two registers, the input of the first of which are connected to the first output of the permanent storage device, and the output is to the first digital-to-analog converter and the input of the second register, the output of which is connected to the second digital-to-analog converter, connected in series to a pulse generator and a counter, the output connected to the third a digital-to-analog converter, two serially connected delay lines, the first of which is connected to the overflow output of the counter and the input of the second register to zero, the output to the input of the first register to zero, and the output of the second line connected to the constant memory polling input device, characterized in that, in order to simplify the generator and disambiguate the functions it produces, the output of the second register is connected to the main address input of the permanent storage device, The second output of which is connected to the counting input of an additionally introduced counter, the output of which is connected to the additional address input of a simple storage device.

27 f5

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