Epson LX-90TM Manuel D’Utilisation

The graphics command requires more than one number to specify

how many columns to reserve because as many as 1920 columns are

possible in graphics printing. Since the LX-90 doesn’t use decimal
numbers larger than 255, the graphics mode command uses two num-

bers for reserving columns.

To figure the number of columns reserved, multiply the second

number by 256 and add it to the first number. Since the command is

set up for two numbers, you must supply two even if you only need

one. When you need less than 256 columns, just make n1 the number

of columns you are reserving and make n2 a zero.

Once you put the printer into graphics mode and reserve the num-

ber of columns you want, your next step is to tell the print head which

pins to fire in each column. There are 256 possible combinations of

eight pins, and you send only one number for each column. The num-

bering system that allows you to use a single number to specify which

of the 256 possible patterns you want is shown in Figure S-1.

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 

To fire the bottom graphics pin, you send 

If you want

to fire only the top and bottom pins, you simply add 

and 1, then

send 129.

By adding the appropriate label numbers together, you can fire any

combination of pins. Figure 8-2 shows three examples of how to calcu-

late the number that will fire a particular pattern of pins.

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