Chapter 3
Programming Overview
This chapter includes the information needed to control the LabelWriter SE450 printer correctly using ASCII Escape commands (referred to as ESC commands throughout this reference guide). Both basic and advanced topics are explained so that you understand how the LabelWriter SE450 printer works.
Programming the LabelWriter Printer
The first step in controlling the LabelWriter SE450 printer is to understand how the printer works.
As an
The ASCII Table contains both "Printable" characters (with values 32 - 127 decimal) which are normally just printed, and
As the printer reads character input from the controlling device, it interprets the data as characters to be printed, or commands, and acts accordingly. This means that sending data and commands to the printer is usually as simple as transmitting the characters from your program to the port to which the printer is connected.
A simple program to print ‘Hello World’ on the LabelWriter printer might look as follows if written in BASIC.
OPEN “COM1:9600,n,8,1” FOR OUTPUT AS #1
PRINT #1, “HELLO WORLD”
The "OPEN..." line above opens the selected COM port for printing and initializes the communication settings while the "PRINT..." line sends the data to the printer.
Commands can be sent to the printer in exactly the same way. For example, if you wanted to change the font which “Hello World” was printed into a
OPEN “COM1:9600,n,8,1” FOR OUTPUT AS #1
PRINT #1, CHR$(27); “T”;
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