There are a couple of pages on the net, describing how to build a serial cable for jailbroken iDevices, e.g. iPhone serial port or Console to routers using the iPad.



So I will just summarize, what I have used:

I started with this nice mini RS232 levels to TTL level converter board serial converter board build with a max3232:




Building a cable with these is simple, just connect power and data lines.

As a connector for the iPad I simply purchased a Dock Extension Extender Cable. I checked that it also has video and audio listed in the descriptions, so the chances that the serial lines are also there are high.

The color code of my cable/extender was like this:

Pin 1 - black - GND
Pin 12 - blue/white - TxD
Pin 13 - brown/white - RxD
Pin 18 - yellow - VCC +3.3V
Pin 21 - red/white - Serial enable - 470kOhm to GND

Together with a Cisco console management cable:

Pin 3 - red - RxD
Pin 4 - orange - GND
Pin 5 - yellow - GND
Pin 6 - green - TxD

The unused TTL-input has to be connected to GND!

The result should look something like this:



Together with minicom on a jailbroken iPad connecting to a Cisco switch works great.

Coming up next: python webserver for web page to serial cable access using pySerial, a socket and some javascript...