This post is divided in points, numbered for convenience as follows: FOREWORD BASICS KNOWN TUTORIALS PRINCIPLES DISCLAIMER and WARNING SERIAL Voltage and TTL levels GROUNDING LOOPBACK TESTS SPEED/DATA BITS/PARITY/STOP BITS/FLOW CONTROL CONVERTERS (or Data Cables) POWERING the converter (or data cable) Thanks and greetings go to ERRATA CORRIGE/additions Final words IMPORTANT EACH of them (with the only possible exceptions of points #12. and #13.) contains IMPORTANT information that may make the difference between success and failure. Please READ ALL of them, without skipping ANY of them, BEFORE posting on the mega-thread and BEFORE doing something that you may later regret with the actual hard disk. ALSO, check this topic by BlouBul: that lists the FGA's (Frequently Given Answers) to recurring questions (mostly posted by people that FAILED to read this read-me-first ) FOREWORD: The scope of this post is to hopefully clear the nth SAME question about topics already asked and replied to on the massive "main" thread: If you have been pointed to this, it means that you failed to read here before posting there yet another time one of those SAME questions/problems. The intended Target: The scope of a thread about problems of Seagate 7200.11 drives is to try and solve two specific problems: BSY - or "busy" state LBA0 - or drive detected by BIOS with size 0 that are caused on a specific model (the 7200.11) by a specific firmware bug:bricking when drive is booted AND Event Log counter is at entry 320, or a multiple of it (i.e. satisfies the expression: ELaddress=320 + x*256 ). More details here: (read about 40 posts starting from the above) Please note how the 7200.11 is also marketed as Maxtor (Seagate and Maxtor are the "same" company nowadays), and also "branded" as HP, IBM and probably a number of other OEM brands. The non-targets: ANY other problem regarding this specific hard disk model (Seagate 7200.11) ANY problem regarding ANY hard disk BUT this specific one (Seagate 7200.11) ANYTHING NOT listed as "target" Notwithstanding the above, this info may be useful to solve a number of similar problems on a whole range of similar hard disks, but in this case information here needs to be checked and verified if applies to your different HD. In other words your mileage may (and WILL) vary. BASICS: Recent hard disks have on board a processor (actually a micro-controller), and an Operating System that allows to issue commands to it. When the hard disk is powered up, to all practical effects it "boots" the internal OS and reads DATA and SETTINGS from a reserved storage area. A number of problems, including the BSY and LBA0 problem on Seagate 7200.11 hard disks are ultimately due to wrong or corrupted data or settings. The above does NOT mean that ANY and ALL problems can be solved by correcting these data, and EXPECIALLY does NOT mean that ANY problem on ANY hard disk can be solved this way. ONLY people with a fairly good knowledge of the innards of a hard disk can use some of the info on the given thread to attempt solving other problems (but those who have the needed knowledge won't need the info in there - CATCH 22). KNOWN TUTORIALS: (first post by gradius2 AND later posts by Aviko - slightly different methods) (tutorial by CarterinCanada - actually RECOMMENDED) PRINCIPLES: The OS on the hard disk can be accessed by means of a serial connection at TTL levels and a communication program (Hyperterminal or similar). A normal PC does NOT have an interface capable of talking directly to the TTL serial BUS on the hard disk, hence an external converter or "data cable" is needed. Typically a desktop PC (not very recent) or a farly old laptop/notebook has a SERIAL or RS-232 port. Most more recent desktops and ANY recent laptop/notebook will only have a USB port. A SERIAL or RS-232 port is preferred as - by default - has ALREADY suitable drivers installed (mapping it to a COM port device) under any Windows OS. The flow of information is the following: Communication program (hyperterminal)->RS232 COM port->RS-232 to TTL Converter->HD TTL BUS->HD OS (and back) If you only have USB ports, the flow of information is the following:Communication program (hyperterminal)->USB port->Installed "virtual" COM port->USB to TTL Converter->HD TTL BUS->HD OS (and back) The RS-232 Standard, AND the TTL levels are usually VERY BADLY implemented by different hardware manufacturers, either at actual hardware level or at driver level, thus it is not in some cases straightforward to establish a communication between the PC and the bricked hard disk. DISCLAIMER and WARNING: Remember that the ONLY value a bricked hard disk has is the DATA on it (yes, those files that you FAILED to backup before). It's up to you to choose (and it depends ONLY on your familiarity with the matters, your current knowledge about electronics and using command line, etc. and on the VALUE you attribute to these DATA) whether: leave this place NOW and ask to a Professional Data Recovery service ask for assistance to a friend or relative with more experience than you have risk the DATA by attempting yourself an unbricking In ANY case, DON'T EVEN THINK about trying this unbricking UNLESS you do have: ready some suitable VERIFIED as WORKING media to copy the DATA over (like a same size or bigger hard disk) completely and fully read AND understood the present post AND the tutorial you are going to use In case of success, DON'T EVEN THINK to consider the unbricked hard disk as "FULLY WORKING" and avoid backing up the DATA (the drive has failed, and like all HD's will fail - again - sooner or later). DO perform BOTH the "Short DST" AND "Long DST" tests using Seagate's Seatools. It is strongly recommended to RMA the drive to Seagate (RMA stands for Return Merchandise Authorization) and obtain a replacement drive. A suitable procedure to do so is detailed here: (read from the above for around 40 posts) There are as many chances the unbricking was fully successful and the drive is in perfectly "normal" working conditions as there are that the unbricking was only a partial success and some other problems remain on the drive. DO NOT be obsessed by "firmware updating", the condition that can cause the problem is an extremely rare event and statistically will happen again, without any firmware update, no sooner than three to six months of intensive use, you have ALL the time in the world to perform the firmware update after the unbricking, and even if it bricks again, you now have the tools and knowledge needed to unbrick it in a few minutes. Upgrading the firmware is a risky operation, DO NOT DO IT unless really necessary, and ONLY do it AFTER you have your DATA back and backed up on another media. If the above wasn't explicit enough, DON'T EVEN THINK of attempting a firmware upgrade on a drive that shows 0LBA or BSY symptoms, in the best case, it will do NOTHING, in the worst case it may put the drive in an "undefined" state from which it may be EXTREMELY difficult to get it in a "fixable" state again. Just DON'T do it! Though already said elsewhere I want to stress the fact that the only actual value you have is the DATA on the drive, the "sane" thing to do, if you are able to unbrick it and recover the data, is to RMA it and have a certified drive back (if under warranty), the next "sane" thing to do is to use the unbricked drive as SECONDARY backup media ONLY (it means that you can use it to store the SECOND copy of your files ONLY). In case you wonder, no matter what you have done all these years, at any given interval, that may vary between daily (mission critical), weekly (common business practice), monthly (hobbyist) you MUST have THREE copies of ANY data you value, an original plus TWO copies, possibly on different kind of media, like: Original on internal hard disk 1st copy on CD/DVD or online storage or external hard disk 2nd copy on external hard disk (possibly physically located/stored somewhere else, NOT in the same room - better if not in the same building - as the original) SERIAL Voltage and TTL levels: Serial communication basically works by sending bits as voltage peaks separated by a time interval. RS-232 sends a "0" by means of a "high level" from +5v to +15v and a "1" by sending a "low level" -5v to -15v. The above is called "negative logic" (0=high;1=low) TTL/CMOS sends a "0" "low" when between 0.2 V and 0.8 V and a 1 "high" when between 2.0 V and 5 V TTL sends a "0" "low" when between 0.35 V and 0.8 V and a 1 "high" when between 2.0 V and 3.3 V The above is called "positive logic" (0=low;1=high) Each circuit/board may use a narrower (or wider) interval for the "high" level, but the "low" level is so narrow by design that having the SAME 0 V level on ALL equipment connected is VITAL. (see below "GROUNDING") You can skip the following links if you trust my word for the above:–transistor_logic Levels of TTL/CMOS and TTL are illustrated here: GROUNDING: Since, as seen above the actual 0's and 1's are obtained by a difference of voltage relative to 0V, it is VITAL, to ensure that TTL level communication works as expected, to have the same 0 V level on ALL equipment involved. This is obtained by connecting ALL the 0 V or "Ground" or "GRN" or "GND" of ALL devices involved together (normally and by convention a black wire is used). Repetita juvant: ANYTHING marked "GND", "GRN", "GROUND" or "-" (minus), or having a black wire, should be connected together. (it would be a smart thing to make sure that you DO NOT use a black wire for Tx or RX AND that using a CA-42 or similar adapter the BLACK wire is actually a ground) I will repeat myself, you NEED a (black) wire connecting: the Hard Disk Drive "Ground" pin the converter "Ground" or 0V pin or connector or wire the (standard PC) Power Supply black wire OR if a battery is used, the - (minus) side/pin of it OR if a separate Power Supply is used, it's black wire or 0V pin or 0v/-(minus) connector or anyway wire marked 0v/-(minus) or connected to anything marked 0v/-(minus)/GRN/GND/GROUND LOOPBACK TESTS: Though it is rare, the actual converter/data cable may be DOA (Dead On Arrival). It is ALWAYS a good idea, before attempting to communicate with the drive, to perform a simple loopback test: Connect the TX and RX of the converter together and see if what you type in the communication program is ECHOed back. More details: SPEED/DATA BITS/PARITY/STOP BITS/FLOW CONTROL: The 7200.11 works with THESE parameters: 38400/8/N/1/N i.e.: Bits per second: 38400 Data bits: 8 Parity: None Stop bits: 1 Flow control: None CHECK them before posting that the PC cannot communicate with the HD. CONVERTERS (or Data Cables): Generic TTL considerations: The hard disk "likes" "real TTL" (the one that has a "high" at max 3.3 V). Nonetheless a TTL/CMOS (that can have a "high" at as much as 5 V) may work. It is unknown whether the HD has a "peaks flattening" circuit of some kind and there are mixed reports. Rule of the thumb: there are NO reports of failures at 3.3V there are a few, not fully confirmed, reports of 5V working Please note that two different converters "labeled" as "5V" may behave differently due to the not fully standard behaviour of some of these circuits. RS-232 to TTL: This is the preferred way. USB to TTL: This is the second preferred way. Data cable (typically Nokia CA-42): This is deprecated. Not because it won't work, but due to the fact that there are so many different versions of these cables, both "original" and "cheap/fakes" that it may be difficult to find the "right" connections, expecially for a newbie. To hopefully clear this point, they do work, most probably ALL of them, original and "fake", do work, IF: the cable is NOT damaged when opening the connector the CORRECT connections are found the cable is NOT damaged in attempts to find the right connections the PROPER driver is found the PROPER driver is PROPERLY installed We have reports of people trying as many as 4 or 5 "CA-42" cables from different sources before finding one that worked for them. As I see it, if you ALREADY have a CA-42 cable lying around in the "things that may be of use some day" drawer, you have nothing to lose in trying it , but if you have to buy one you'd better invest some more money in a "proper" TTL converter, known to be always working. POWERING the converter (or data cable): The converter (or data cable) is an active component and needs to be POWERed. Some converters draw power from the "PC side" (RS-232 or USB bus side). <- in this case you need NO external Power Supply. Some converters draw power from the "other side" (TTL side). <- this means, that since on the TTL side you will connect to the HD, you will fall in condition below. Some converters need an external Power supply (a FULLY CHARGED battery will do). Generally speaking supplying 0V and +5V will work. Most adapters will work with as low as 0V and +3V. A single 3V battery or two common 1.5V may do in the latter, but ONLY if they are FULLY CHARGED/NEW, if they fall below 2.9 or 2.8 V it simply won't work. A good idea is to use 3 or 4 rechargeable 1.2V batteries (again FULLY operational/charged): 3x1.2=3.6V 4x1.2=4.8V Another good idea if you have a Desktop PC is to get the power from it's cables: Black=0V Orange= 3.3V Red= 5V A known exception is this specific board: that switches output levels autosensing the voltage you power it with, thus you need for this a voltage around 3 V for this to work properly. The "main" thread: is choking full of links and photos and help given for a number of different data cables (mostly "NOKIA") ad converters, both USB and RS-232. TAKE YOUR TIME on it if you have doubts, most probably the solution is ALREADY there, BEFORE posting a request for help. Thanks and greetings go to: Besides gradius2 and Aviko, and CarterinCanada, you should be grateful to a number of other members that helped in gathering the info and in supporting other members in the megathread, most notably: mundy5 Videoripper and a particular mention for:BlouBul that has, besides helping a lot of people, compiled the excellent FGA's: (should have I forgotten mentioning anyone, please PM me and I'll add your name to the above list) ERRATA CORRIGE/additions: Should you feel something in this post is incorrect, missing or both , please PM me with your suggestions/integrations and I'll edit the post accordingly. Final words: DON'T PANIC! (assume the above to be written in large, friendly letters) There are very good chances that your precious DATA (yes, still the same that you failed to backup properly before) is still there and can be recovered. Rest assured that DATA does not: evaporate rot waste away by itself. If you start fiddling in semi-random ways with the HD, it is on the other hand very possible that YOU will make the DATA unrecoverable , so, once again: DON'T PANIC DON'T FRET DON'T FREAK OUT but: TAKE YOUR TIME in understanding the info presented here and in the linked to topics, and AFTER having done your best, if you still have doubts, do ask for help or assistance in the given "monstrous thread": IMPORTANT It is VERY likely that you cheated and skipped some (if not most) of the above, if you - by any chance - skipped over the second part of point #5, here are the REALLY IMPORTANT bits of it:   However it would be appreciated if you would go up to point #5 and read in it's entirety. jaclaz P.S.: post edited to stress the fact that: you DO NOT want to attempt updating the firmware on drives that show 0LBA or BSY symptoms. you DO NOT want to use normally a CA-42 or similar "mobile data cables" as it is likely you will encounter problems with them. (thanks to mkcheznous for pointing out how the above points were not clear enough) P.P.S.: Point #7 slightly modified (thanks to SnakeByte2 for pointing out possible problems in the wording) inorder to better convey the suggestion to GROUND  each and all  pieces of equipment involved in the procedure.