What Registers Must Be Loaded Before A Memory Write Operation?

Read and Write operations in Memory

A memory unit stores binary information in groups of bits called words. Data input lines provide the information to be stored into the retentivity, Data output lines carry the information out from the memory. The command lines Read and write specifies the management of transfer of data. Basically, in the memory organization, there are $2^{l}$ retentiveness locations indexing from 0 to $2^{l}-1$ where l is the address buses. We tin can describe the memory in terms of the bytes using the post-obit formula:

$N = 2^{l} Bytes$
Where,
l is the full address buses
Due north is the memory in bytes

For example, some storage can be described beneath in terms of bytes using the above formula:

            1kB= ii^x            Bytes  64 kB = two⁶            x 2¹⁰            Bytes        = 2¹⁶            Bytes  4 GB = 2²            10 2^x(kB) ten two¹⁰(MB) x 2¹⁰            (GB)       = ii³²            Bytes

Retentiveness Address Annals (MAR) is the address register which is used to shop the accost of the retention location where the operation is being performed.
Memory Data Annals (MDR) is the information annals which is used to shop the data on which the operation is existence performed.

Memory Read Operation:
Retention read operation transfers the desired give-and-take to address lines and activates the read command line.Description of memory read operation is given below:

In the above diagram initially, MDR tin contain any garbage value and MAR is containing 2003 memory address. After the execution of read pedagogy, the data of retentivity location 2003 will be read and the MDR volition go updated by the value of the 2003 retentivity location (3D).
Memory Write Operation:
Memory write operation transfers the address of the desired word to the accost lines, transfers the data $.25 to exist stored in memory to the data input lines. Then it activates the write command line. Description of the write operation is given below:

In the in a higher place diagram, the MAR contains 2003 and MDR contains 3D. Afterwards the execution of write pedagogy 3D will be written at 2003 memory location.