A Simple Electric Motor: Variable speed drives in the industry employ a simple electric motor as their drive motors mainly because they enjoy several specific advantages, such as overload capacity, smooth speed control over a…
8288 Bus Controller: Figure 5.37 shows the 8288 bus controller which is used in the maximum-mode operation of 8086 CPU. This IC receives four inputs such as SÌ…2, SÌ…1, SÌ…0Â status signals and CLK from 8086.…
8279 Keyboard Display Controller Interfacing with 8085: Fig. 14.98 shows the 8279 Keyboard Display Controller Interfacing with 8085 in I/O mapped I/O technique. Here RD and WR signals are activated when IO/M signal is high,…
8279 Block Diagram: Fig. 14.84 shows the 8279 Block Diagram. It consists of four main sections CPU interface and control section Scan section 8279 Keyboard section Display section 1.CPU Interface and Control Section: This section…
8259A Programmable Interrupt Controller: 8259A Programmable Interrupt Controller - Microprocessor-based system design requires many I/O devices such as keyboards, displays, sensors and other components. These devices should receive servicing in an efficient manner from the…
8259 Programmable Interrupt Controller: The 8259 Programmable Interrupt Controller requires two types of command words. Initialization Command Words (ICWs) and Operational Command Words (OCWs). The 8259 Programmable Interrupt Controller can be initialized with four ICWs;…
8259 Block Diagram: Fig. 14.71 shows the internal 8259 Block Diagram. It includes eight blocks : data bus buffer, read/write logic, control logic, three registers (IRR, ISR and IMR), priority resolver, and cascade buffer. Data…
8257 Pin Diagram: Fig. 14.61 shows 8257 Pin Diagram. Data Bus (D0-D7) : These are bi-directional tri-state signals connected to the system data bus. When CPU is having control of system bus it can access…
8257 DMA Controller: In microprocessor based systems data transfer can be controlled by either software or hardware. Upto this point we have used program instructions to transfer data from I/O device to memory or from…
8255A Programmable Peripheral Interface: 8255 is a programmable peripheral interface IC and is a multiport input/output device. This is a general-purpose programmable I/O device, which may be used with many different microprocessors. There are 24…
