User`s guide

SET LS
VECTOR=n
Modifies the printer handler to use n as the vector of the line printer controller.
The value you supply for n must be an even octal address below 500. This option
enables you to set a special vector value in the line printer handler itself, without
having to modify the handler source code and reassemble. Use this option if you
have installed the printer controller at a nonstandard address.
WIDTH=n
Sets the printer to width n, where n is a decimal integer between 30 and 255
inclusive. RT–11 ignores any characters that print past column n. The default
is 132.
RT–11 Command Descriptions 249