Epson LQ 1050 User Manual - Page 87

Graphics Pin labels To tell the printer which pins to fire in each column, you first divide each of the vertical columns into three sections of eight pins each and consider each section separately. Since there are 256 possible combinations of the eight pins in each section, you need a numbering system that allows you to use a single number to specify which of the 256 possible patterns you want. This numbering system is shown below: 128 2 16 8 4 1I To fire any one pin, you send its number. To fire more than one pin at the same time, add up the numbers of the pins and send the sum to the printer. With these labels for the pins, you fire the top pin by sending 128. To fire the bottom pin, you send 1. If you want to fire only the top and bottom pins, you simply add 128 and 1, then send 129. By adding the appropriate label numbers together, you can fire any combination of pins. Below are shown three examples of how to calculate the number that will fire a particular pattern of pins. 128 H 128 64 32 32 16 88 iii 64 16 88 128 I 128 i; 16 8 ; 2 1281 3 - 74 : s 1 134 With this numbering system, any combination of the eight pins adds up to a decimal number between 0 and 255, and no numbers are duplicated. 4-11