Connection of the Console Interface on CISCO ASR 920 Series Routers

While using the CISCO ASR-920-24SZ-M router, Moduletek Laboratory observed that the console port of this device differs from that of other CISCO devices, the physical shape of the interface is USB-A, the next, let's learn together how to connect the console port of this device.

We tried to use the standard USB to DB9 serial cable, but it couldn't be connected; in addition, we also added an RJ45 adapter to the USB-to-RJ45 cable according to the instructions in the installation manual, converted it to a DB9 connector, and then connected it to the host, but still couldn't get it to connect. From the installation manual, the console interface with a physical USB-A form factor is not actually a USB interface; instead, it is an interface compliant with the TIA/EIA-232F standard.

Figure 1 Interface Rate Configuration Error Message

We found a share about the console interface of the CISCO ASR 920 series routers on the Cisco Community. According to the share, the pinout order of the cable is as follows;

Figure 2 Cable Pin Arrangement

Next we make a usable Console cable by ourselves according to the above cable order; prepare an ordinary USB cable, cut off one end of the connector, here I use a Micro USB cable, cut off the Micro_USB connector, peel off the outer skin, you can see that there are four copper wires, the color of which are red, white, green and black;

Figure 3 USB cable cut off one end

Arranged the copper wires according to the above pinout order, insert them into the corresponding positions of the RJ45 connector, and crimp with a crimping tool. A "click" sound indicates that the crimping is in place.

Figure 4 Access to the RJ45 crystal head

Use a RJ45 to DB9 female adapter connected to the router through the serial port after the cable production is completed , you can also use the RJ45 adapter to the standard DB9 serial cable.