PCL interpretor moves to the next row when encountering a line feed character. By default, the raw height is 1/8 inch. Although this setting is good for text printing, the line spacing is too big for the data matrix bar codes.

To print the data matrix barcode correctly using our PCL font, you need to adjust the row height at the beginning of the barcode printing. This can be done via the Vertical Motion Index (VMI) command.

<ESC>&#C

where # is the number of 1/48 inch increments between rows. For example, 6 means that there are 8 lines per inch.

The VMI values vary from font to font. The VMI values for our fonts are as follows:

mrvdatamatrix_12.sfp --> VMI=2.34
mrvdatamatrix_14.sfp --> VMI=2.73
mrvdatamatrix_16.sfp --> VMI=3.12
mrvdatamatrix_18.sfp --> VMI=3.51

For example, if you are using mrvdatamatrix_18.sfp, invoke the command at the beginning of the bar code printing:

<ESC>&3.51C

After you have done printing the barcode, you can switch to the normal VMI line spacing using the command:

<ESC>&6C

You also need Morovia DataMatrix Font Encoder to calculate the barcode string. Currently the encoder can only run on Windows platform. Check Morovia support for platform supported. The PCL soft fonts are generated from true type version at font size 12, 14, 16 and 18 points. If you need a special size we can generate for you free of charge. Write to <support@moroiva.com> with your order number.