Printer Commands

The Model 8900 Series Printers receive commands from the host computer in the form of ASCII control character codes and escape- sequence codes. In response to these commands, the printer performs one or more operations defined by the command set of the currently selected emulation mode. Chapters 4 through 8 describe the standard emulation modes.

An example of a control character command common to all character sets and all emulation modes is the line feed (LF) character. This control character (designated by hexadecimal code 0A or decimal code 10) causes the printer to advance the paper or form to the next print line. To invoke the line feed operation, the host computer sends the 8-bit code (00001010) identified as the LF character.

An escape-sequence command is a sequence of two or more characters that always begins with the ASCII escape (ESC) control character designated by hexadecimal code 1B. The ESC control character signals the printer that one or more succeeding characters are an escape-sequence command.

An example of an escape-sequence command common to all standard emulation modes is the Set Form Length command ESC C n. This command contains the following elements.

qESC — the ASCII control character that signals the start of an escape sequence

qC — an ASCII character that identifies the escape sequence as a form length command

qn — a decimal variable that can be set to a range of values to specify the form length in number lines

Note: Decimal values of variables are designated by lowercase italic letters. ASCII characters and number values of variables are designated by uppercase italic letters.

Character Sets and Global Commands 3-18

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Epson 8900 Series manual Printer Commands