Auto picks up call hack - Cisco SPA301

This modified IP phone for automatic picks up call on the TRX side of remote.

Cisco SPA301 connectors(Edit)

  • 4p4c Handset
      -------
     |    ---|  tp389  mic +2V
    |     ---|  tp390  sp
    |     ---|  tp391  sp
     |    ---|  tp392  mic GND
      -------
    
  • Hang up switch
     |
    o| n/c
    o| n/c
    o| 3,3V
    o| input
     |
    ----
        |
    eth |