Hard Disk Drive Firmware.
Hard disk drive firmware is in the form of micro-code and data parameters written to the HDD electronics and to the hard disk drive data storage media. The micro-code takes the form of small executable programs that independently control the functionality of the device and the transfer of data to and from the formatted areas of the device storage media. The Hard Disk Drive Firmware manages the device behaviour and factory settings, any hard drive that comes out of the factory and is in use in a computer or server has firmware installed on it.
Hard Disk Drive Firmware Failure
This microcode must boot from power on and execute a series of self-checks and operational procedures without which it will not function. If a Hard Disk Drive Firmware becomes faulty or corrupt then the hard disk drive will fail to function and will either appear unresponsive or present a clicking sound.
Hard Disk Drive and Computer BIOS and UEFI.
A computer will boot up under the control of the Basic Input Output System (BIOS ) or Unified Extensible Firmware Interface (UEFI). UEFI is a standard firmware interface for PCs, designed to replace BIOS (basic input/output system). PC BIOS is limited to a 16-bit processor mode and 1 MB of addressable memory space compared to UEFI which uses 64-bit addressing to directly access all of the machine’s memory. Microsoft ties its MBR partition table to the firmware used and UEFI is now a practical necessity in order to boot Windows on disks with a capacity of 2TiB or over.
Computer Hardware Boot-up.
For a computer to successfully boot using BIOS or UEFI all its essential hardware components must report that they are working properly. Failure of any essential hardware module will likely result in a failed boot sequence. From power on the computer CPU initializes and reads the BIOS instruction sequences. The first instruction received is to run the Power On Self Test (POST), this checks the BIOS chip, RAM and battery health and if these checks are OK the CPU will initialise and check the inventory of installed hardware devices, graphics card, hard drives, keyboard , mouse etc that are registered in BIOS. Once the POST has determined that all components are functioning properly and the CPU has successfully initialized, the BIOS looks for an Operating System to load. The Operating System is stored on a computer hard disk drive and will load into RAM under the control of the CPU.
Hard Disk Drive Initialisation.
The BIOS or UEFI boot process issues a number of notification and health check commands to the Hard Disk Drive Interface. In turn the Hard Drive firmware microcode will respond having performed and completed a number of hard disk drive housekeeping tasks. This successfully completed, the BIOS will then typically instruct the loading of the operating system from the Hard Disk Drive label C. Once the OS initializes, the BIOS copies its files into memory and the OS basically takes over control of the boot process. Now in control, the OS performs another inventory of the system’s memory and memory availability and loads the device drivers needed to control peripheral devices such as printers, optical drive, mouse and keyboard. This is the final stage in the boot process, after which the user can access the system’s applications and perform tasks.
Hard Disk Drive Firmware Service Area.
The firmware service area of a hard disk drive is resident in its control Integrated Circuitry on its PCB and also located on the hard disk platters. This internal microcode controls the functionality of the hard disk drive and the way the device stores data.
Hard Disk Drive Firmware Modules Examples
There are a number of hard disk drive firmware modules, the following is an example:
Zone Table:- Location Parameters Speeds up read and write
ATA Module :-Used to access factory mode.
Defect Image :- Records Defects.
S.M.A.R.T Table:- Records operational parameters and exception errors
Module Map:- Log of Modules, Drive Config., LBA,S/N number, Defect maps.
Factory Settings:- Model number, S/N number, LBA, Password
P-list:- Permanent Defects, List of unusable areas of formatted recording media.
G-list :- Grown Defects., List of unusable areas of the formatted recording media during operation.
Hard Disk Master Boot Record.
The Master Boot Record (MBR) is the information in the first sector of a hard disk that identifies how and where an operating system is located so that it can be loaded into RAM. The Master Boot Record includes a table that locates each partition that the hard disk has been formatted into. In addition to this table, the MBR also includes a program that reads the boot sector record of the partition containing the operating system to be booted into RAM. In turn, that record contains a program that loads the rest of the operating system into RAM.