Compact Data Acquisition System Research Articles

A compact scanning tunneling microscopy control and data acquisition system based on a Macintosh II workstation

A compact system based on a Macintosh II workstation for scanning tunneling microscopy (STM) control, data acquisition, and image display and processing is presented. To access the versatile analog electronics and the piezo scanner of our STM, a multifunction board (MacAdios II) is employed as an interface. The on-board timer/counter permits well defined time intervals between each tip movement and subsequent data acquisition. For on-line control and image display of scanning processes an efficient code was written in Pascal and C. To achieve simple and user-friendly operation, the program takes advantage of so-called mouse–window–desktop techniques supported by the Macintosh operating system. The entire code has a modular structure and therefore facilitates easy replacement of existing modules or implementation of additional ones.

Data-acquisition system of the reversed field pinch device REPUTE-1

The new, compact data-acquisition system of the reversed field pinch device, REPUTE-1, is reported. Its distinctive feature is high flexibility and easy handling. The interface between the computer and measurement devices is CAMAC. The computer and the CAMAC devices are connected to a CAMAC byte serial highway that transmits setup parameters and acquisition data. The computer carries out setup of CAMAC devices and data acquisition automatically by use of CAMAC parameters and the acquisition data base. The maintenance tools for the data base are also provided. The computer system, which consists of a ‘‘TOSBAC DS-600,’’ has been in operation for REPUTE-1 since 1985.

A Compact Magnetometer Data Acquisition System with Accurate Chronometer

A compact data acquisition system in use for a geomagnetic pulsation study has been constructed. The system is composed of a data processing system controlled by a microprocessor, cassette tape recorder, chronometer and short wave radio receiver. The system is programmed to calibrate the chronometer every five minutes by receiving a standard time signal, such as JJY (Japan), WWV (USA) and so on. The system improves a signal to noise ratio of the radio waves by signal stacking processes to minimize errors in the chronometer calibration. Even in a very weak signal, the system can discriminate a second pulse. The calibration accuracy is 10msec, including circuit signal delay when a radio propagation delay is neglected. The system is programmed to sample three component magnetometer signals at intervals of 3 sec and can store 1.3 Mbytes of data in a C-90 cassette tape which is equivalent to ten-day data. The system is suited for an unmanned operation at a station remote from the standard signal station.