• Firmware Rrepair for
• Laptop Hard Drive
• Desktop Hard Drive
• External Drive
• RAID - Array of drives
• FLASH Memory & SSD

How Hard Drive works: Firmware on Disk Platter and PCB

The hard disk drive (HDD), like a computer, has its own "operating system" known as an internal firmware. That internal service software (or microcode) must boot itself: instantly, error-free, right off the drive is powered on computer's start up.

If the boot goes OK, the internal software makes your hard drive being a live part of the computer, as only from this point the hard disk is able to interact with other computer's parts on their universal digital language.

If, by any reason that microcode fails booting on the drive, the computer will not be able to identify the failed hard drive. The computer just skips on such broken drive.
Let's take a closer look on the simplified scheme of the initialization processes happen under the hood of hard drive.

On the picture above the green rectangle stands for the major electronic part of hard drive, it is a drive's motherboard with its own processor and RAM, well-known as PCB (Printed Circuit Board). PCB is not only set of chips on the green board, it also has some little part of hard drive firmware, written in their chips and processor.
But the major part of firmware is located inside the drive, on the spinning disks inside the drive's frame.

The coloured disk on the picture represents the magnetic hard disk, a spinning platter inside the drive's body.

The major part of that disk (blue zone on the picture) is LBA (Logical Block Addressing) sectors, what everyone uses on the hard drive. LBA sectors can be accessed from the computer and used as storage data media for user's data. The attendant software that includes operating system is located in LBA sectors, too.

However, there is a hidden service tracks with sectors (brown zone on the picture), known as Service Area, where locates the rest of internal software, designated only to serve for normal and flawless work of the drive. This internal software, or hardware microcode, refers to hard drive firmware, S.M.A.R.T info, the translator module (keeps records about defective sectors or the whole defective tracks, it helps keeping the order in the system of addressing physical sectors to logical-LBA), tuning parameters for heads, and much more.

When the hard drive is powered on, the small part of firmware on PCB is starting the whole process of booting the drive. It sends the command to power on the motor, move the heads over the spinning surface to catch the synchronizing marks to stabilize the speed.

Then the microcode on the service zone starts loading into the drive's memory.
That piece of loaded code from disk platter must be matched to the firmware code from the circuit board. Otherwise the integrity of the whole drive’s software system will be violated.

If something goes wrong with loading the whole piece of microcode (on PCB’s part or on disk’s part), the drive will fail to start normally. The hard drive can stop its motor, or start clicking, or just freeze, i.e. stop responding to any commands from outside.

Generally, PCB is the most dependable part of the hard drive. The most problems come from damaged mechanical parts, especially, from ultra sensitive heads. The most dangerous condition of the damaged hard drive for its data is the damage to the magnetic layers of the spinning disk platters.

Some of the hard disk models require the unique firmware burned into original PCB, that's why we require that the damaged hard drive must be presented in one original (parts, labels, etc.) unit for data recovery process. No matter how bad it may visually look, the burned PCB must not be replaced by any others from another hard drives, the recovery procedures demand the original PCB only! We will take care of the rest.

How to start with Databe data retrieval service: