148 APPENDIX B: C ABLE SPECIFICATIONS AND PIN- OUTSPin-outsNull-Modem Cable 9-pin to RS-232 25-pinPC-AT Serial Cable 9-pin to 9-pinScreenTxDRxDGroundRTSCTSDSRDCDDTRScreenRxDTxDGroundRTSDTRCTSDSRDCDShell325786141327420568Webcache 1000/3000Cable connector: 9-pin femalePC/TerminalCable connector: 25-pin male/femaleonly required if screenalways requiredrequired for handshakeScreenDTRTxDRxDCTSGroundDSRRTSDCDScreenDCDRxDTxDDTRGroundDSRRTSCTSShell43285671Shell12345678Webcache 1000/3000Cable connector: 9-pin femalePC-AT Serial PortCable connector: 9-pin femaleonly required if screenalways requiredalways requiredrequired for handshakerequired for handshakeRequired for handshake
