The command for printing a postal barcode in ZPL is :
^BZo,h,f,g,t
The parameter t can have the following options :
0 = Postnet bar code
1 = Plant Bar Code
2 = Reserved
3 = USPS Intelligent Mail bar code
I am aware what 0,1,3 are, but I can not seem to find out what option 2, or the Reserved option, represents. Anyone know what this option might be?
It means "reserved for future use". It is not explicit, but if you search through the ZPL manual looking for "reserved" they use it in a lot of commands that are tied to standards bodies as they expect changes in standards over time. ^CI, ^HW, ^MM, ^RF, ^RS all have reserved parameters. Even some of the character sets list "reserved" slots.
The Zebra engineers are just being proactive to be able to accommodate changes to standards.