Tanmay Chakrabarty

(i) Required Bit Format of command byte A:            So the bit format will be 10010000.           (ii) Required Bit Format of command byte A:  So the bit format will be 1010×11×.

Command Byte A and Command Byte B:

Pin-Out Diagram of 82C55A: I/O Ports: It has three I/O ports, A, B and C. Each of these has 8 pins.             CS : This is used to select the 82C55A for programming and reading or writing.             A0 & A1: Register selection is done using the A0 and A1, which select … Read more

Handshaking:  Handshaking is a I/O control method to synchronize I/O devices with the microprocessor. As many I/O devices accepts or release information at a much slower rate than the microprocessor, this method is used to control the microprocessor to work with a I/O device at the I/O devices data transfer rate. Example:  Supposing that we … Read more

Memory Mapped I/O and Isolated I/O are two methods of performing input-output operations between CPU and installed peripherals in the system. Memory mapped I/O uses the same address bus to connect both primary memory and memory of hardware devices. Thus the instruction to address a section or portion or segment of RAM can also be used to address … Read more

          Port : A port is an adapter which enables a system to communicate with its input/output devices. Using port user can connect I/O devices and use them. There various types of port such as parallel port, serial port etc.             Differences Between Fixed Port and Variable Port Addressing : Fixed Port … Read more

Hamming Technique (7,4) : In this case, we will have 4 bits of data and we will add 3 bits of redundant with the data by calculating the 4-bit data. For example, taking a 4-bit data as, The encoder will encode the data as follows , Thus the decoder will receive, 0 1 1 0 … Read more

Error Detection or Parity Check Method : A general way to detect errors is to append a special bit to every word. One popular technique employs a single check bit called parity bit. The parity bit is append to an n-bit word X = x0, x1,….., xn-1  to form the (n+1)-bit word X* = x0, x1,….., … Read more

Error: Various factors like manufacturing defects to environmental effects cause errors in computation. Such errors frequently appear when information is being transmitted between two relatively distant points within a computer or is being stored a memory unit. Shortly, error is missing of bit or bits in data due to change and various effects. Error Detection: … Read more

Comparing Different Types of Memory Devices in Terms of Cost & Performance: The best way to measure the cost of a memory device is the purchase price of a complete unit of its. Let C be the price in dollars of a complete memory system with S bits of storage capacity. The cost c of … Read more