Cisco Console to Null Modem Serial Adapter

Step 3 Wire the RJ45 jack

Now comes the tricky part. We need to match the wiring in the jack to be configured for RS232 null modem with full handshaking. I found this page very helpful when I was wiring: RS232 serial cables pinout

Some colors might vary on the Cisco cables (I checked the pile we had), but not much. White and gray are the only colors that I noticed changed in my stack of cables. You might want to grab your trusty multimeter and test the cables for your pinout diagram.

See the wiring chart picture for details.

Comments

[Creepy Kid]

I am uncertain on how to read this chart. Is the Orange on the Cisco cable the RJ-45 equivalent of Blue, because thats immediately to the right, or the RJ-45 equivalent to Orange-White, because they share the same number?

[cowen]

Simple you read the chart the way the cable was crimped. Do not mind the color in the cable the position of the color is the important part. Every Jack uses the 568a/b standard the author chose the 568B pin out to use. To actually color code this to a jack would assume that CISCO uses the same colors all the time. This would be a 90% true statement. Looking at the crimp end with the gold pins facing you record the colors and what pin that color goes to should follow the above chart then you need to match that position to the correct position on the CAT5 jack using a 568B configuration as the chart shows above. I build these cables daily you just need to record and know that the jack has to match the end you cut off. The author also put the correct null modem swaps of hand shacking into the cable on the re build. pin 7 never got to pin 1 in a network cable. you just need to not think about 568a/b cable standards here and what does it take to connect and switch handshaking and data flow for RS232.