Precautions For Two-Dimensional Code Printing; Two-Color Printing; Nv Memory - Epson TM L90 Technical Reference Manual

4.8 Precautions for Two-Dimensional Code Printing

This printer can print two-dimensional codes. The following two-dimensional codes can be
printed.
❏ PDF417
❏ QR Code
❏ MaxiCode
Note the following for two-dimensional code printing.
❏ The two-dimensional code recognition ratio changes depending on the module width, print
density, environmental temperature, roll paper (thermal paper) type, reader performance,
etc. Therefore, pre-check the recognition ratio and set the operating conditions to satisfy the
restrictions of the reader.
❏ For PDF417 (two-dimensional code) printing, it is recommended to set the height of one
symbol to three to five times greater than the module width. It is also recommended to set
the overall height of the code to more than 5 mm (approximately).

4.9 Two-Color Printing

This printer can print two colors. For the two-color printing method, refer to the corresponding
data of OPOS, Printer Driver, or ESC/POS commands.
Note:
Depending on the print pattern, the colors of two-color printing may not be clear (Example: Red and black
checkered pattern). In this case, the print result may be improved to some degree by setting an unprinted
space between the first and second colors or by adjusting the print density. (The amount of space depends
on the print density and paper.)
The reliability of two-color printing differs from that of single-color printing. Refer to "Reliability" on
page 6-5 for details.

4.10 NV Memory

NV memory is embedded in the printer. Please use NV memory with attention to the following:
❏ The following restrictions apply when performing nonvolatile memory operations
(including data store and delete).
• The paper feed switch must not be used to feed paper.
• The real time command must not be executed.
• The ASB status will not be sent, even when the ASB function in ESC/POS command is
set to enable.
4-16 Application Development Information Rev. B