HP ProBook 6450b

Serial (select models only)
Pin Signal
1 1 Data carrier detect
2 Received data
3 Transmitted data
4 Data terminal ready
5 Signal ground
6 Data set ready
7 Request to send
8Clear to send
9 Ring indicator
Universal Serial Bus
Pin Signal
1 +5 VDC
2Data
3 Data +
4Ground
196 Chapter 8 Connector pin assignments