在一些案例中硬盤(pán)有一個(gè)或者多個(gè)的磁頭出現(xiàn)故障，但是硬盤(pán)依然可以正常初始。但是當(dāng)我們嘗試訪問(wèn)用戶區(qū)時(shí)硬盤(pán)提示錯(cuò)誤，無(wú)法訪問(wèn)用戶扇區(qū)。
In some cases a drive with one or more malfunctioning heads can finish the initialization process without any visible errors. But when we try to read user area it results in error and no user data can be read. For example it can occur when one or more heads have problems with writing.

當(dāng)至少一個(gè)系統(tǒng)磁頭是好的情況下 ，我們通過(guò)以下操作流程訪問(wèn)用戶數(shù)據(jù)
The procedure allows to get access to data on all normally working heads of the drive when SA and at least one of system heads are OK.

該方法的主要思路是用一個(gè)好的磁頭替代有故障的磁頭
The main idea of this method is to to trick the drive calibration procedure through substitution of a normal head instead of a malfunctioning one. Consequently it works with drives using two or more heads.

關(guān)于系統(tǒng)磁頭損壞的情況下的數(shù)據(jù)訪問(wèn)方法 將在下一篇文章中講解
Also it can be applicable when one of the system heads is damaged. In such cases the patient drive may produce clicks, knocks and turn down the spindle. This case will be reviewed in details in the next article.

本案例中 我們將恢復(fù) WD20EARS-00MVWB0? 硬盤(pán)的數(shù)據(jù)（系統(tǒng)磁頭良好）。硬盤(pán)可以就緒但無(wú)法訪問(wèn)用戶區(qū)，我們?cè)谡ＤＪ较逻M(jìn)行以下操作。
In this example we recover WD20EARS-00MVWB0 drive with non-system head damaged. The drive goes READY but do not give access to its User Area. So we use the procedure in Normal mode.

Here the procedure:

啟動(dòng)硬盤(pán) ，等到硬盤(pán)就緒
We turn the drive ON and wait until it goes READY

點(diǎn)Utility Autodetect 按鈕 進(jìn)入實(shí)用程序
Then press the Utility Autodetect button and double-click the utility

點(diǎn)Autodetect 按鈕 自動(dòng)發(fā)現(xiàn)硬盤(pán)家族? 啟動(dòng)實(shí)用程序
Now press Autodetect button and check that Mode and Drive Family are chosen correctly and press the Utility Start button

硬盤(pán)初始化正常，沒(méi)有報(bào)錯(cuò)，SA 區(qū)可以訪問(wèn)，硬盤(pán)ID 正確
As we can see the drive initialized without any errors, SA is accessible and drive ID is correct

在這里我們可以看到硬盤(pán)共有六個(gè)磁頭 ，都處于工作狀態(tài)
Also here we can see that the drive has 6 heads and all of them are ON

用Sector Edit 菜單 檢測(cè)用戶區(qū)是否可以訪問(wèn)
To check that the User Area is accessible we can use Sector Edit tool.

在這里我們發(fā)現(xiàn)無(wú)法訪問(wèn)用戶區(qū)，程序報(bào)錯(cuò)
As we can see here we do not have access to the User Area and drive returns ERROR status

現(xiàn)在進(jìn)行一次軟復(fù)位 ，讓硬盤(pán)復(fù)位
Now I give a Soft Reset command to the drive to set it in Ready status

等待硬盤(pán)再次 就緒
And wait until it becomes ready again

現(xiàn)在我們需要檢測(cè)SA模塊， 以確認(rèn)用戶區(qū)無(wú)法訪問(wèn)的原因是否與SA模塊有關(guān)
Now we need to check the SA modules to be sure that problem is not in them

工具?Tools -> Utility extensions實(shí)用程序 擴(kuò)展-> Modules directory模塊目錄
To do that go to Tools -> Utility extensions -> Modules directory

然后按選擇模塊讀取方式按鈕
Then press Select Modules Reading Method button

并選擇ABA 讀取Copy0
and select Read by ABA Copy 0

然后按SA檢查按鈕
Then press SA checking button

檢查所有模塊是否被選中，然后按OK
Check that all modules are selected and press OK

檢查完成后，我們來(lái)看看結(jié)果
When the checking is completed we look at the results

我們可以看到，所有關(guān)鍵模塊（A類(lèi)和B類(lèi)）都是正確的
As we can see here all the critical modules (A and B category) are correct

(not all the modules are shown on the picture)

所以現(xiàn)在我們檢查Copy 1模塊
So now we check the Copy 1 modules.

再次按選擇模塊讀取方式按鈕，現(xiàn)在檢查copy1。然后按OK。
Press Select Modules Reading Method button again and now check Copy 1 box. Then press OK.

再次按SA檢查按鈕，檢查所有模塊是否被選中，然后按OK
Again press the SA checking button, check that all modules are selected and press OK

我們可以看到Copy 1的模塊也正常的，所以應(yīng)該不是模塊引起的問(wèn)題
We can see that Copy 1 of modules is also OK so the problem is not in the modules

(not all the modules are shown on the picture)

問(wèn)題不在SA模塊中。所以我們需要檢查磁頭。
The problem is not in SA modules. So we need to check the heads.

我們必須找出哪些磁頭損壞了，所以讓我們進(jìn)行磁頭測(cè)試。
We have to find out which of the heads are damaged so let’s run the Head test.

點(diǎn)擊Tests -> Service information -> Work with service area -> Heads test
To do that we go Tests -> Service information -> Work with service area -> Heads test

在這里，我們可以看到硬盤(pán)的6個(gè)磁頭。我們來(lái)檢查所有磁頭。然后按OK。
Here we can see all 6 heads of the drive. Let’s Check all of them. Then press OK.

選擇日志選項(xiàng)卡以查看進(jìn)程
Choose the Log tab to see the process

這里我們可以看到測(cè)試結(jié)果
Here we can see the test results

在這里我們可以看到正在測(cè)試哪個(gè)磁頭和測(cè)試階段。
And here we can see which head is being tested and stage of the test.

在頭部測(cè)試的第一階段，它將特定的數(shù)據(jù)寫(xiě)到盤(pán)片上的特殊位置
On the first stage of the head test it writes the specific pattern to the special place on the platter

在測(cè)試的第二階段，磁頭讀取數(shù)據(jù)并檢查它與寫(xiě)入是否匹配
And on the second stage of the test the head reads data and checks that it matches with the pattern

這里我們看到結(jié)果：磁頭0是正常的
Here we see the result: Head 0 is OK

磁頭1是也正常的
Head 1 is also OK

但是在這里我們可以看到磁頭2寫(xiě)出現(xiàn)問(wèn)題
But here we can see problems with writing on Head 2

它顯示為ERR和ABR信號(hào)燈的閃爍，之后BSY信號(hào)燈常亮幾秒鐘
It appears as blinking of ERR and ABR flags and right after that the BSY flag stays ON for few seconds

一旦我們發(fā)現(xiàn)當(dāng)前的磁頭部寫(xiě)入（或讀到）有問(wèn)題，我們可以按“跳過(guò)”按鈕來(lái)檢查其他磁頭
Once we understood that current head has problems with writing (or reading) we can push Skip button to check other heads

跳過(guò)后我們?cè)谌罩纠锟梢钥吹?磁頭2 是寫(xiě)入有問(wèn)題的
Right after skipping the head we see the result in log: Head 2 has writing problems

磁頭5,6和7已成功通過(guò)檢查。
Heads 5, 6 and 7 has successfully passed the checking.

所以磁頭檢測(cè)的結(jié)果是2頭壞了? 其他磁頭是好的，我們需要在RAM 磁頭位圖里用其他好的磁頭來(lái)替代損壞的2頭
So only Head 2 malfunctioned and it needs to be spared in RAM with other good working head

點(diǎn)擊Tests -> Service information -> Work with RAM -> RAM head map editing
To do that we go to Tests -> Service information -> Work with RAM -> RAM head map editing

如果您在此步驟中收到錯(cuò)誤消息，那么您應(yīng)該嘗試手動(dòng)將Loader上傳到RAM中。
If you get an Error message on this step then you should try to manually upload Loader into RAM.

現(xiàn)在我們可以看到 RAM 里面的磁頭位圖了
Here we see our current head map in RAM.

在這里我們用一個(gè)其他的磁頭號(hào)來(lái)代替損壞的磁頭2 ，用于替代的磁頭號(hào)是任意的（可以是2之外的任意一個(gè)， 在這里我們選用磁頭5）
To spare your malfunctioning Head 2 we have to replace its number in map with number of any working head and press OK. In this example I choose Head 5

現(xiàn)在我們嘗試使用扇區(qū)編輯工具訪問(wèn)用戶區(qū)
Now we try to get access to User Area using Sector Edit tool

看來(lái)運(yùn)氣不太好
And no luck again

修改完后忘了點(diǎn)軟復(fù)位，所以導(dǎo)致訪問(wèn)扇區(qū)出錯(cuò)
It occurred because I forgot to give Soft Reset command to the drive.

進(jìn)行軟復(fù)位
So let’s press the Soft Reset button

等到驅(qū)動(dòng)器就緒
Wait until the drive is Ready

并再次運(yùn)行扇區(qū)編輯工具。
And run Sector Edit tool again.

經(jīng)過(guò)軟復(fù)位后，我們可以訪問(wèn)扇區(qū)了? ，意味著用戶區(qū)可以訪問(wèn)
Now it worked! We can see the data in the sector. So now we can read User Area.

所以現(xiàn)在我們可以切換到Utility Selection窗口并運(yùn)行Data Extractor。不要關(guān)閉西數(shù)專(zhuān)修程序！
So now we can switch to the Utility Selection window and run Data Extractor. DO NOT CLOSE THE WD UTILITY NOW!!!

現(xiàn)在我們創(chuàng)建一個(gè)新任務(wù)
Now we create a new task

選中Make Data copy選項(xiàng)
with Make data copy option checked

建立磁頭位圖通過(guò) Service menu -> Build heads map
To build a new head map we go to Service menu -> Build heads map

我們需要所有LBA磁頭位圖，所以只需按應(yīng)用按鈕
We need head map for the whole LBA space so just press Apply button

這里我們可以看到，磁頭位圖構(gòu)建的過(guò)程已經(jīng)完成
Here we can see that the process of heads map building is completed

我們可以去任務(wù)參數(shù)進(jìn)行調(diào)整
And we can go to Task params to make adjustments

選擇Heads map標(biāo)簽
Now we go to Heads map tab

我看到了所有磁頭，選中的將用于讀取數(shù)據(jù)
Here we see the heads. Those which are checked will be used for drive image reading

取消選中故障磁頭2。
Uncheck malfunctioning head 2.

要特別注意這里的邏輯磁頭號(hào)（0,1,2,3,4,5），但在WD實(shí)用程序中，我們使用的是物理頭數(shù)（0,1,2,5,6,7）。所以你不應(yīng)該記住數(shù)字，而是記住磁頭的位置
Pay special attention to the fact that heads here have logical numbers(0,1,2,3,4,5) but in the WD utility we worked with physical heads numbers(0,1,2,5,6,7). So you should remember not the number but the position of the head in stack

現(xiàn)在我們可以從選中工作的磁頭開(kāi)始讀取硬盤(pán)的鏡像
Now we can start reading the image of the disk from working heads

故障磁頭的數(shù)據(jù)只有在我們更換整個(gè)磁頭后才可以獲得。但它是下一篇文章的主題。
The data from the malfunctioned Head we can get only if we replace the whole head stack. But it is a topic for one of the next articles.

轉(zhuǎn)載請(qǐng)注明：成都千喜數(shù)據(jù)恢復(fù)中心 » 使用PC-3000 for HDD在RAM中編輯西數(shù)硬盤(pán)的磁頭位圖，虛擬磁頭恢復(fù)西數(shù)硬盤(pán)數(shù)據(jù)