Lexmark X925 Forms and Bar Code Card Technical Reference Guide - Page 55

• Aspect ratio = 1:4 Note: Using this aspect ratio, the bar code symbol is constructed as nearly as possible with a height-to-width ratio of 1:4. PCL 5 Data: ESC&x16W0001 04 02 0008 02 00 00 00 01 04 0000 0000 ESC&y39WHere_are_39_bytes_of_data_to_be_encoded Note that the bar code descriptor data is in bold. Each digit is a hex nibble. Two nibbles make each byte and thus there are 32 nibbles. Each descriptor field is separated by a space to make the header more readable. These spaces will not be sent with the data. Bar code descriptor for MaxiCode The following is the header definition of the bar code descriptor for MaxiCode: Bytes 0-1 2-3 MSB Symbology ID byte 1 (00x) Mode LSB Symbology ID byte 2 (02x) Reserved Symbology ID bytes 0 and 1: (Required = 00 02x) These two bytes signify the symbology. Since most descriptors have different sizes and information, all bar code descriptors must reserve the first two bytes for the symbology ID so the remaining bytes can be interpreted accordingly. For MaxiCode, these two bytes must be 00x and 02x. Mode: (Default = 02x) This field designates what mode to use when interpreting the input data. Valid modes are (in hex):. Value 02x 03x 04x 05x 06x Description Structured carrier message with numeric postal code Structured carrier message with alphanumeric postal code Standard symbol with standard error correction Full symbol with enhanced error correction Reader program with standard error correction MaxiCode notes: Depending on the mode, the input data sent with the Transfer Bar Code Data command must follow these rules: • For all modes, the input data must start with a label-number field and number-of-labels field. Both fields are one digit in length, and are terminated with either a comma or group separator (GS, ASCII 29). Two-dimensional bar codes 52