Cisco 7941G - Unified IP Phone VoIP Administration Manual page 278

Network and Access Port Pinouts
Table D-3
Pin Number
8
Note
Cisco Unified IP Phone 7961G/7961G-GE and 7941G/7941G-GE for Cisco Unified Communications Manager 6.1
D-4
Access Port Connector Pinouts (continued)
"BI" stands for bi-directional, while DA, DB, DC and DD stand for
"Data A", "Data B", "Data C" and "Data D", respectively.
Appendix D Technical Specifications
Function
BI_DC-
OL-14620-01