MS-DOS: Need to know

MS-DOS: Need to know Part 1

Now that Microsoft has open sourced MS-DOS it’s a good time to look at filing systems, blocks and the FAT and how they are used. Let’s explore the basics of a DOS – Disk Operating System. There is a big problem with disk drives. No, not the constant running out of space that we used to suffer from, but the deeper computer science and engineering problem of actually making them useful at all. We are so familiar with disk drives being delivered to us in a usable form that it is first necessary to go back to the raw hardware to see what the problem is. In a hard disk drive…

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Double Data Rate

The present day RAM is built on the Synchronous Dynamic Random Access Memory using the Double Data Rate specifications and hence they are called SDRAM of DDR1, DDR2, DDR3  and the latest DDR 4 versions. They work on the basis of double pumping, dual pumping or double transition process. They are able to provide two data transfer for each clock cycle. The first in the category of RAM is the DDR or DDR1 RAM. DDR or DDR 1 belongs to the first generation in the SDRAM technological evolution. It is characterized by enhanced prefetching, strobe based data bus, double transition clocking, low voltage signalling, Stub- series Terminated logic-2 etc. Comes with…

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