Using the Linux Shell in Compex APs
This page describes how to use the Linux shell in Compex APs.
Hardware that can be used
Any one of the following hardware can be used.
Serial Converter Cable
Serial converter cables can be purchased together with Compex APs. One end is the RS-232 serial port. The other end is a set of 4 wires, usually coloured red (5V), green, blue, and black (ground). This plugs into the 4 protruding serial pins on the Compex board (WPJ342, WPJ344, WPJ531, and WPJ558). These are located about 4mm from the edge of the board. This is to differentiate it from the 4 USB pins that are flush with the edge of the board.
If your computer does not have serial port, you may purchase a USB-to-serial cable. This can be found in electronic shops or online.
While your computer is online, please connect the USB-to-serial cable to your computer. It should be plug and play. The driver should be installed automatically.
Next, open the Device Manager in the Control Panel to see the COM number. For example, “Prolific USB-to-Serial Comm Port (COM5)” under “Ports (COM & LPT)” means that you should specify “COM5” as the Serial line name in PuTTY.
An Ethernet cable can be used to connect your PC to the AP.
Over the Network
As long as you can ping to the AP, you can login to its shell.
Programs that can be used
PuTTY and MobaXterm can be used.
Serial Port Settings
The following settings can be used if you are connecting to the board via the serial port. Please specify the COM number that you have found earlier e.g. COM5.
- Baud rate / bits per second = 115200;
- Data bits = 8;
- Stop bits = 1;
- Parity = None;
- Flow control = None;
Apply the same settings in the Windows Device Manager.
The serial console prints out all system messages, including kernel panic.
You may obtain the root password from Compex Sales.
This password can be used to login to the Linux shell. For added security, one may login and run passwd to change the password, followed by reboot.
When connecting via the network, the messages printed are fewer than the serial console. Kernel panic is not shown.