Your network printer most likely support the SNMP (Simple Network Management) Protocol.
For further reading about this protocol, look
here.
Take a look at Net-SNMP. An open source tool which can send SNMP queries and is considered to be very powerful.
The following page [
^] contains all codes that can be sent to printers. These code are called OIDs.
The OID you probably need would be: ".1.3.6.1.2.1.43.11.1.1.9"