Describe the various types of data transfer the bus supports

A bus supports various data transfer types.

(i) Read

(ii) Write

(iii) Read-modify-write

(iv) Read-after-write

(v) Block

(i) Read: For read operation, there is typically a wait while the data is being fetched from the slave to be put on the bus.

Address

Access

Data

Read (Multiplexed) Operation

(ii) Write: For write operation, the master puts the data onto the data bus as soon as the address has stabilized and the slave has had the opportunity to recognize its address.

Address (first cycle)

Data (Second cycle)

Write (Multiplex) Operation

(iii) Read-modify-write: A Read-modify-write operation is simply a read followed immediately by a write to the same address.

Address

Data Read

Data Write

(iv) Read-after-write: Read-after-writer is an indivisible operation consisting of a write immediately by a read from the same address.

Address

Data Write

Data Read

(v) Block: In block data transfer, one address cycle followed by n-data cycle.

Address

Data

Data

Data