Cisco Console RJ45 to DB25 Pin

Pinout of the Cisco RJ-45 console to DB-25 adapter (part 29-0810-01) mapping all 8 asynchronous RS-232 signals for terminal access to Cisco routers.

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The Cisco RJ-45 to DB-25 console adapter (Cisco part 29-0810-01, also identified as CFDTE) connects the 8-pin RJ-45 console port found on Cisco routers and switches to a PC or terminal fitted with a 25-pin D-sub serial port. The adapter is used in conjunction with the blue flat rollover cable (CAB-500RJ) and carries a subset of EIA/TIA-232-F asynchronous RS-232 signals. The Cisco console port is wired as DTE and operates at a default rate of 9600 baud, 8 data bits, no parity, 1 stop bit, and no hardware flow control.

25 PIN D-SUB FEMALE 25 PIN D-SUB FEMALE to the Computer)

RJ45 MALE CONNECTOR RJ45 MALE CONNECTOR To the Cisco router

RJ45DB9
RTS1
DTR2
TXD3
GND4
GND5
RXD6
DSR7
CTS8

Signals

  • RTS — Request To Send; output from the Cisco console port (RJ-45 pin 1), maps to DB-25 pin 5
  • DTR — Data Terminal Ready; output from the Cisco console port (RJ-45 pin 2), maps to DB-25 pin 20
  • TXD — Transmit Data; serial data output from the Cisco router (RJ-45 pin 3), maps to DB-25 pin 2
  • GND — Signal ground (RJ-45 pins 4 and 5), both map to DB-25 pin 7
  • RXD — Receive Data; serial data input to the Cisco router (RJ-45 pin 6), maps to DB-25 pin 3
  • DSR — Data Set Ready; input to the Cisco console port (RJ-45 pin 7), maps to DB-25 pin 6
  • CTS — Clear To Send; input to the Cisco console port (RJ-45 pin 8), maps to DB-25 pin 4

Notes

  • The DB-25 column in the pin table above lists the DB-25 pin numbers (not DB-9 pin numbers as the table header suggests).
  • The full RJ-45 to DB-25 signal mapping is: RJ45-1→DB25-5 (CTS), RJ45-2→DB25-20 (DTR), RJ45-3→DB25-3 (RxD), RJ45-4 and RJ45-5→DB25-7 (GND), RJ45-6→DB25-2 (TxD), RJ45-7→DB25-6 (DSR), RJ45-8→DB25-4 (RTS).
  • The Cisco console port does not support hardware flow control; RTS/CTS are wired but inactive by default. The AUX port on Cisco devices does support hardware flow control.
  • The companion adapter for DB-9 terminals is Cisco part 74-0495-01 (CFDTE91); the two adapters share the same blue rollover cable.
  • The same RJ-45 console pinout (pin 1=RTS, 2=DTR, 3=TD, 4=SigGnd, 5=SigGnd, 6=RD, 7=DSR, 8=CTS) is used across Cisco routers and switches and is also adopted by Sun Microsystems (Netra/SunFire), Juniper, Lantronix, and Nokia VPN gateways.

References

Category:Serial Cables