----- HAM/LINK Sec: 5 By: SAM*OH2AZG Bytes: 2,872 Date: 4/09/86 14:40 Num: 658 Total Downloads: 5 Title: EASY TO USE GRAPHICS NOTATION Keywords: GRAPHICS, DRAWING, DIAGRAMS, CIRCUIT DIAGRAMS ----- Drawings are essential in communicating about electronics. Circuit diagrams and other drawings are almost impossible to convey using text. There are several graphics standards, among others NAPLPS (ANSI X3.110) and GKS (ANSI X3.124). These are, however, quite complicated and difficult to implement. The following bare minimum graphics notation is easy to convert for plotters and graphic displays in personal computers. It can be read and drawn even without a computer. This graphic notation is made using graphic tablets or other graphic encoders and a simple program. It is compatible with existing text communi- cation, filing and text processing programs. It is relatively effective as regards storing and transmitting. However, the ease of use having been an overriding goal in its development. The graphics are drawn on a grid with 399 by 399 points. Points are numbered from -199 to +199. Point -199,-199 is at the left lower corner, point +199,-199 at the right lower corner, and point 000,000 at the center of the screen or paper. Drawings are made using the following commands: M x,y move pen or cursor from present point to point x,y without drawing anything (pen up) P x,y draw a line from present point to point x,y (pen down) R reset, move cursor or pen to point 000,000, middle of the screen, i.e. to origo, and set linetype to zero X finish the drawing, move cursor or pen to point 000,000 and leave it there in non-drawing or invisible position L n select linetype n, number n being from 0 to 15, numbers 0 to 7 representing an unbroken line with colors, and numbers 8 to 15 representing dotted line with the same colors; devices without colors can draw various dotted lines T "text" write "text" beginning at present point lower left of the first character; only horizontal text is possible, seven by seven points per character; charac- ter values from 32 (space) to 126 (tilde) are allowed (* comment *) comment does not affect drawing in any way; it is only for the human reader There could be more drawing commands, but it would make the implementation of programs more complicated. For instance, there could be a commands for drawing a circle, filling a defined area with a given color and repeating a given series of drawing commands (macro). This graphic notation is intended for, though not limited, to this system, and other telephone, packet radio, RTTY and AMTOR based ham communication systems. Your comments are appreciated. Please, send comments and ques- tions to me (SAM*OH2AZG) or write REPLY here. You can also reach me also as Q-SAM at FINHUT.BITNET. 73, Sakari M. Mattila, OH2AZG