Bidirectional Printing In this manual, we describe the action of the print head as moving from left to right, as a typewriter does. During its normal operation while printing in the draft mode, however, the MPS 1000 prints bidirec- tionally. That is, the print head goes from left to right on every other line. On the other lines it reverses everything and prints right to left. By reversing both dot patterns and printing direction, the MPS 1000 produces a line that is correct and looks no different from a line printed from left to right. It does this to save time. Otherwise, the time the print head takes to go from the right margin back to the left would be wasted.
The intelligence of the printer takes care of all the calculations for bidirectional printing, so you don't have to be concerned about it. Do your part of the work as if the printer will be printing from left to right on each line and let the MPS 1000 do all the necessary calculations. Changing Pitches (IBM Mode Only) In addition to pica, in which there are 10 characters per inch, the MPS 1000 can also print in other widths, or pitches. It does so by reduc- ing the distance between pin firings. In elite mode it prints 12 charac- ters per inch. In condensed mode it prints slightly more than 17 charac- ters per inch.
The pattern of the dots is not changed, but the horizontal space between them is reduced. In Figure 2-2 are enlargements of four sample letters in each of the three pitches. These letters are chosen to show how the MPS 1000 prints letters that are uppercase and lowercase, wide and narrow, and with and without descenders such as the bottom part of the y. 26