SU636640A2 - Time interval-to-numeric code converter - Google Patents

Description

The proposed transducer of the time interval into a digital code can be used in various instruments of measuring instrumentation and computing, in particular, in high-precision instruments for measuring time intervals. Known Converter time interval to a digital code on avt.svid. No. 292173, which is the closest in technical essence to the proposed converter. The result of the conversion is given in the form of a digital code taken from the outputs of the counting cells of the high-order counters, and the code from the unit outputs G1 of the counting cells of the lower-order bits. The result of the conversion can be expressed by the relation: where K is the number of transfer pulses received at the input counter whose higher bits of the counter: 0 is the period of the reference frequency (1 clock generator; k is the number of single states at the outputs of the P triggers of the lower order) the counter; l is the magnitude of the shift of the pulses of the reference frequency on the VB1 INPUTS of an I clock generator relative to each other. In a known transducer, the conversion result taken from the higher bits is the positional parallel binary code and the code is The rest of the bits are nonpositional, as a result the total digital code is non positivating, which represents a great inconvenience to the {M1 processing of the results of the converter by computing devices that work with positional codes. Besides, for an odd value of H, an error of conversion is equal to dpr. t ;; - t;, escf "-kn-z-1-a (p-K-1) 1.

The aim of the invention is to reduce the conversion error.

To do this, a decoder is additionally added to the converter, the first additional group of P – 1) elements AND and an additional group of Itl elements OR are added, and the inputs of the decoder are connected to the unit and zero outputs of the counter cells of the lower bits of the pulse counter, a (And -1) the outputs of the decoder are connected to the first inputs of the elements of the first and second additional groups, the second inputs of the elements of the first additional group are connected to the zero output of the input counting trace of the higher bits of the pulse counter, the second inputs of elements AND of the second additional group are connected with c) the unit M1 output of the input counter of the higher bits of the pulse counter, and in the first additional group the outputs of the first and second elements AND are connected to the inputs of the first and second elements OR of the additional group, respectively, the output of the third element. And - with the inputs of the first two elements OR, ..., the output (t -3) of the element AND - with the inputs of all the elements OR, except the second, the output () of the element AND - with the inputs of jBcex elements OR, except the first, the output (and -1) of the AND element - with the inputs of all the OR elements, and in the second additional group the output of the first AND element is connected to the inputs of all the OR elements of the additional group, the output of the second) AND terminal - to the inputs of all but the first OR elements , the output of the third element I - to the inputs is all but the second, the elements OR,.,., the output (about 3) -th. of the second and second elements OR, the output (AND -2) of the element AND to the inputs of the second segment of the OR, the output (G7 -1) of the element AND to the input of the first element OR, with m 1,2,3 ... , rt. In FIG. 1 shows the proposed converter; 2 - block diagram of a variant of the converter on the example of a four-stroke generator; FIG. 3- time diagrams of the converter operation for two values of the time interval T; (. 12).

Oak contains a semi-automatic pulse generator of the reference frequency 1, the first group T1 of the elements I 2, the counting pulses of the counter of pulses 3, the second group of the 2 2 elements I 4,

the element OR 5, the counting cells of the higher bits of the pulse counter 6, the decoder 7, the first and second additional groups of (T -1) -th elements AND 8.9, an additional group of elements OR 1O

Consider the operation of the converter on the example of its specific implementation for a four-stroke generator.

Pulses of the reference frequency from the outputs of the generator 1, shifted relative to each other by the value of tg (diagrams 3-6 through the first group of 4 And 2 elements, transmitting pulses only during the time interval T, arrive at the information inputs of the corresponding triggers of the least significant bits 3, where memorized (plots 7-10,16), Single and zero outputs of the triggers of the low-order 3 counting cells are connected to the inputs of the second group of elements 4, at the outputs of which transfer pulses are formed (plots 11, 12, 17, 18), which through the element OR 5 (plots 13, 19) arrive at the information input of the input counting 5gchiki 6 older bits of the counter.

At the same time, if the number of transfer pulses is even, then the zero output of the input counter cell 6 higher bits of the counter after the end of the time interval will be in the unit state (plot 14), and if odd, then in the zero (plot 2O). At the same time, the signals from the single and zero outputs of the triggers 3 are fed to the inputs of the decoder 7, containing twelve AND elements (11-22) and three OR elements (23-25), the outputs of which are the outputs of the decoder 7 (in Fig. 2, the decoder inputs are marked a a, b, c, b, c, d, and the outputs of the decoder -A, b, c).

The decoder 7 is built this way.

(A-obcd-f abc abed- (abed, B "abed + abc3 -t- abed tobcd,

Claims (1)

1. USSR author's certificate №. 292173, class O 06 J 3/00, 1969, And l 1 " Step fz fa ./  Bbtx element / Howl elements 3 gave uHmepiana 7 one. . zlementob Outlet 5 (UG Pulse Transfer) . (Lots of counting cell At the higher order you. And deiMU pamopa 7  Sttf. OVnavo az u / gementob f / fffff intell a 7 } 8i1 lemento8 Out source s (carry pulses}  Howl fxoffHoU countershare senior bit Per Pitchfork A 8eshifter 7