Logical Control System for a Seismic Section Builder
Abstract Generated abstract
This paper describes a logical control system for the PSR-II seismic section builder, an output device intended to convert digitally processed seismic information from universal computers into analog records suitable for interpretation. The authors outline the need for automated high-speed output to photographic material and magnetic tape, then present a control scheme that extends the earlier PSR-I system by managing magnetic-head movement, trace grouping, playback scale switching, and cathode-ray tube movement. Implemented with Ural-10 logic elements and coincidence circuits, the system supports automatic operation of the computer and PSR-II complex during direct output and rerecording from magnetic tape to photographic material.
Full Text
LOGICAL CONTROL SYSTEM FOR A SEISMIC SECTION BUILDER
Yu. M. Achkasov, S. S. Krykin, V. V. Timofeev, V. N. Sorokin
(Presented by the scientific and technical seminar of the Research Institute of AEM)
To increase the speed and accuracy of processing seismic information, it is expedient to use universal digital computers (BESM-4, Minsk-22, M-222, etc.). However, the use of computing machines for processing seismic information is difficult if they are not equipped with special input and output devices. In most cases, information is output in digital form onto magnetic tapes and magnetic drums. For the convenience of analyzing the processed seismic information, it must be presented in analog form. Therefore, the creation of high-speed output devices for digital computers that make it possible to obtain information in analog form suitable for further interpretation is an urgent task. Output devices expand the capabilities of digital computers and automate—
Fig. 1. Logical control circuit of the PSR-1
—processed seismic information, it must be represented in analog form. Therefore, the creation of high-speed output devices for digital computers that make it possible to obtain information in analog form suitable for further interpretation is an urgent task. Output devices expand the capabilities of digital computers and automate-
...the processing process. At present, special output devices have been created for universal digital computers—seismic section builders (PSR-I, PSR-II)—which completely automate the process of outputting information from the machine.
These builders make it possible to construct time sections of the earth’s crust on photographic material, and also on magnetic tape of the NG001 type (PSR-II), which permits multiple rerecording of the processed information, freeing machine time. Recording on magnetic tape is carried out sequentially by a single magnetic head. This method eliminates the need to adjust the identity of recording channels in the case of parallel recording and makes it possible to carry out recording and playback with minimal distortions.
In the present work a logical control system (LCS) for the PSR-II digital-computer complex is considered; it is a further development of the logical control system of the PSR-I (Fig. 1).
Fig. 2. Timing diagram of the operation of the logical control system
The logical control system, in addition to the functions that it performed in [1], controls the movement of the magnetic head. The movement of the magnetic head to the next track occurs on the signal “beginning of the photographic-paper fastening zone” (Fig. 2). This must occur only after the recording or reading mode of the preceding trace; therefore the signal for forming the movement of the magnetic head appears in the case when trigger \(T_2\) prepares the coincidence circuit \(I_4\). The system is implemented on “Ural-10” elements.
Electronic switching of the number of traces in a group and of the playback scale has been introduced into the circuit; it is implemented in the form of coincidence circuits made on module B-1. This makes it possible to carry out switching directly in the circuit by applying zero potential from the control panel. Such switching reduces the effect of interference on the operation of the circuit.
To control the movement of the cathode-ray tube, an “OR” circuit is used. The electromagnet is switched on by the signal “beginning of the photographic-paper fastening zone” and remains switched on if recording is taking place, since a signal from trigger \(T_2\) is applied to the “OR” circuit.
The logical control system considered here provides automatic control of the digital-computer—PSR-II complex in the modes of outputting information from the digital computer and rerecording from magnetic tape onto photographic material.
References
-
Yu. M. Achkasov, V. A. Beinarovich, Yu. I. Potekhin, L. S. Udut, A. D. Kozhukhovskii, S. S. Krykin. Features of a control system for photoregistering output devices for a digital computer. Izv. TPI, vol. 211, Publishing House of TSU, 1970.
-
S. B. Stopsky. Logic circuits on semiconductors and their application. “Energiya,” 1969.