Recently, I have a problem where when I tried to update Ubuntu package via apt-get, it shows HTTP 401 proxy error related. Just a note, I’m running VM using my office network which has an enterprise web proxy servers.
Recently, I was searching for rollover cable that used to connect your PC/laptop to your switch via console port. It took me for a while searching this kind of cable in Low Yat Plaza, KL. Here, you can find variety of electronics stuff from PC hardware to servers stuffs.
But, it was hard for me to find this cable. After several visit to Low Yat, I managed to find the cable together with DB9 to USB converter. As you know, the rollover cable is using serial to ethernet cable. So, this post will guide you on how to install the driver and connect your rollover cable to your switch from Mac OS X.
So, for the first step, you should have rollover cable that looks like this:
After you’ve done downloading and extracting the driver, just click at .pkg file and proceed to install the driver. Reminder, make sure you restarted you machine after installing the driver in order for system to take effect:
Then, connect/plug-in the rollover cable to DB9 to USB converter. Then connect the converter USB to you Mac. After all has been connected, click on Apple logo on top left menu bar, click About This Mac, on Overview tabs, click System Report. Ensure that you DB9 converter is connected:
After restart, you can verify if the driver has successfully installed and loaded to the system by using this command:
$ kextstat | grep prolific
$ ioreg -c IOSerialBSDClient | grep usb
Now finally, you need an application which will talk to the serial port. We’ll using Terminal app on Mac OS X. On Mac, the file which maps to the port is /dev/cu.usbserial. Once all the cable has been connected, run this command to start connecting to you switch is:
Recently, I’ve flashed my MR3020 in attempt to make my own Wifi Pineapple. But.. You know. Shit happen. :p
In other word, i screwed up my MR3020 and bricked it. All the LED is keep on blinking, some is on and not blinking, and the network is getting connected and disconnected randomly. Guess that’s a sign you’ve mess up with the device. XD
But I’m lucky because you still can recover the device via serial console and tftpd32 method. (yeay!)
Bear in mind that this method will VOID your warranty. So, don’t do this unless you willing to sacrifice for the sake of knowledge. 🙂
Things that you need:
Tftpd32: A free tftp and dhcp server for windows, freeware tftp server. Very efficient for booting over LAN.
PuTTY: SSH and telnet client, free and open-source terminal emulator, serial console and network file transfer application.
So, as you can see, my USB-UART converter come with 6 ways header pin for interfacing. The voltage selector must set to 3.3V since the TL-MR3020 router have its I/O pins working at 3.3V.
Connection Diagram * Do not connect the router VCC to USB-UART VCC, it may break your adapter or your router
TL-MR3020 | USB-UART | COLOR ------------|---------------|----------- GND | GND | BLACK RX | TXD | GREEN TX | RXD | YELLOW
For the picture of the connection diagram, refer to first picture above.
So, in my case, my MR3020 is version 1.9. As you can see picture above, mine doesn’t have any serial port to connect to using female jump wire. So I use female (attach to USB-UART) to male (attach to MR3020) as picture below:
Take note that I only put the resistor and jumper wire without soldering. You can do a soldering to your jump wire and resistor to the port with in this tutorial, I skip with that. :p
After you have all things in place, you can start installing the UC00B (USB-UART) driver to your computer. After finished, restart your computer, and check your Device Manager. You should see something like this:
which indicated that the driver and the converter is detected by computer and the driver is properly installed.
Setting up network IP address Assign a static IP address to the computer, using IP address 192.168.1.2 since the router IP address is 192.168.1.1. No need for Internet connection in this process.
REMEMBER! Ensure that you have disable you windows firewall. Or else, the next step will might not work.
Install OpenWRT from the U-Boot console Download the latest OpenWRT firmware and save it to C:\Program Files\Tftpd32 (Tftpd32 default installation folder) as shown in figure below:
You also can click the “Show Dir” button and check if the file is there or not.
Run Putty, select Serial option, on Serial Line, I’m using COM3 since my USB-UART driver detected as COM3, for Speed option, I use 115200. Then click Open. Example like picture below:
After that, power up your MR3020. On Putty console, you should see something like this:
U-Boot 1.1.4 (Aug 17 2012 - 15:21:03)
AP121 (ar9330) U-boot
DRAM: 32 MB
led turning on for 1s...
id read 0x100000ff
flash size 4194304, sector count = 64
Flash: 4 MB
Using default environment
No valid address in Flash. Using fixed address
No valid address in Flash. Using fixed address
: cfg1 0x5 cfg2 0x7114
: cfg1 0xf cfg2 0x7214
ATHRS26: resetting s26
ATHRS26: s26 reset done
Autobooting in 1 seconds
The moment after you see “Autobooting in 1 seconds“, type in word “tpl” immediately.
If everything is correct, you should see “hornet>” in your console. if you missed it, close and open back your Putty, follow the instruction above until you see the word “hornet>“
Now you are in U-Boot-console, as it shows “hornet>” on your console. Now enter the following commands: setenv ipaddr is the MR3020 IP address, setenv serverip is the computer IP address,