I've just managed to recover my Stupid Barracuda 7200.11 HDD. I used the USB to RS232 TTL converter I bought from the following ebay link.
It costs only US$1.72, but took about 7 weeks to be shipped from Hong Kong to Singapore.
The cable works perfectly when I did the loop test by shorting the green and white color cable.
To connect to the HDD, I need to remove the black casing at the end of the cables, and covered it with insulative tapes individually. After that I followed the instructions and connect it to the HDD. Initially, it cannot communicate -> no respond after entering CTRL-z at the hyperterminal. Then, I swapped the green and white cable, also did not respond. I noticed the metal end of the cable could be too loose to have a good contact with the HDD pins. I then used a plier to make the metal sleeve narrower to ensure good contact when plug in. After this, it responded when I type CTRL-z.
I used the Avico procedures but without the optional codes initially. After the last instruction (m0,2,2,0,0,0,0,22), there was no message return after waiting for more than 10 minutes.
I then, power off the HDD. and repeat the procedures from the beginning (including removing the screws and re-inserting an anti-static plastic in between the PCB and heads connector). This time, I used the optional part and after typing the last instruction, it immediately return the Max Wr Retires = 00, Max Rd .......... message. Great !
I am now able to get back all the data and will update the Firmware.
Thanks to all the contributors in this forum !
Edited by swc2008, 28 October 2014 - 08:27 AM.