Ascii module programming

Hello everybody. I am currently trying to send ZPL commands to a Zebra zt410 from a compactlogix L30ER with v30 studio 5000. I am connected to the printer via a 1769 ascii module channel 0. I have already saved a format to the printer and I am able to print from the command prompt in zebra setup utilities using ^XA ^XFR:xxxx.ZPL^XS ^XFxxxxx^XS^XZ. I have entered each character into the sint tags that are created in the tag database under local:3:O.TxData and I have switched the style to ascii from decimal and all my characters check out. I have entered the correct length in TxDataLength tag. I haven't written any code yet I am just testing by changing the value in local:3:O.Ch0TxID. The printer does nothing. The status indicator for Tx0 does nothing and the input tag for TxDataSent is still 0. Any help is greatly appreciated.

PS. I am in the process of acquiring the network connect and special firmware to do this via ethernet but I thought I would try serial in the meantime.