With IPHost Network Monitor you can run simple snmp requests against a HP device in your network.
serialUse
serial Use
1.3.6.1.4.1.11.2.3.9.3.1.1.10
What the serial port is being used for. Note that primary and auxiliary use indicate that the serial port is 'connected' to TCP ports 9100 and 9101 respectively.
Back to hp-700rx MIB page.
IPHost Network monitor allows you to monitor serialUse on Hewlett Packard device via the SNMP protocol. Download IPHost Network Monitor (500 monitors for 30 days, 50 monitors free forever) to start monitoring Cisco wireless switches right now.