PSI Matrix PP 803 Benutzerhandbuch Seite 195

Appendix A System Interface Description
Additional Information
After Power-ON DTR is activated and the printer is ready to receive data.
DTR is deactivated when the interface buffer has only space left for 256
more characters. Further incoming data will be stored until the
interface buffer is full. All data sent in addition will get lost. DTR is
activated again if there is a free interface buffer space of 512
characters.
DTR is immediately deactivated, if local mode is entered.
It is activated again, if local mode is left and a minimum of 512 bytes
interface buffer is available.
A-5