SELCIR: SYSTEMS ENGINEERING LABORATORY CIRCUIT-DRAWING PROGRAM

Abstract : SELCIR, Systems Engineering Laboratory Circuit Drawer, enables the user to draw electronic circuit diagrams on a CRT display. All graphical manipulations are performed locally in a PDP-9, which, together with a 339 display scope, forms a remote terminal to an IBM 360/67. SELCIR scans the drawn network and transmits the topology of the network diagram to the central computer. The 360 the analyzes the network and sends back results which are displayed in the form of graphs. To enable the user to express himself naturally, the graphical manipulations emphasize the user of the light pen rather than push buttons. Also the user can stop at any point to correct mistakes or make changes. Finally, many constraints on the drawing process enable him to quickly make a neat looking diagram.