Graphics
Pin labels
To tell the printer which pins to fire in each column, you need a numbering system that separately identifies each of the eight pins as shown below. This system allows you to specify all 256 possible pin combinations with a single number.
1 2 8
ii 16
:
2
1 I
To fire any one pin, you just send its number to the printer. To fire more than one pin at the same time, add up the numbers of the pins and send the total. Using the pin labels shown above, 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, and send 129.
By adding the appropriate label numbers together, you can fire any combination of pins. Below are three examples of how to calculate the number that will fire a certain pattern of pins.
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. Before you can use these numbers in a graphics program, however, you need to know the format of the graphics command.
Software and Graphics