Epson 4100 manual Data Byte Values of Command Parameters, Zeros and Ones, DEC Control Commands

136 Universal Control Commands

This formula for determining n1 and n2 is used for graphics commands and for specifying a range of characters in some commands (such as the commands to map or download characters).

DATA BYTE VALUES OF COMMAND PARAMETERS

A source of confusion arises because three of the conventions used to specify command parameters use numbers. For example, 48 could be a decimal data byte, a hexadecimal data byte, or an ASCII character representation of a two-byte sequence, 4 followed by 8. The conventions used in the emulations of the 4100 printer are specified in the following paragraphs.

Universal, Epson, and IBM Control Commands

Univeral, Epson, and IBM control commands use (n) to indicate the decimal value of a single data byte. For example "(n) = (75)" is the data byte identified by decimal number 75. This is the same data byte identified by hexadecimal number 4B and ASCII character K.

DEC Control Commands

DEC control commands use (n) to indicate an ASCII character or sequence of ASCII characters. For example, "(n)=(75)=(7)(5)=7 5" is a two-byte sequence. The decimal numbers are 55 and 53, and the ASCII characters are 7 and 5.

ZEROS AND ONES

Since upper case "O's" and zeroes look similar, zeroes in control commands are shown with slashes.

Since lower case els (l) and ones look similar, lower case els in control commands are shown as scripted els ( ! ).