Interfacing of 8257 with 8085

Interfacing of 8257 with 8085: Fig. 14.68 shows the interfacing of 8257 with 8085 in I/O mapped I/O technique. In slave mode, RD and WR signals are activated by CPU…

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Operating Modes of 8257

Operating Modes of 8257: The Operating Modes of 8257 can be programmed to operate in following modes : Rotating Priority Mode : In rotating priority mode, the priority of the…

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8257 Pin Diagram

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…

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Features of Microprocessor 8257 DMA Controller

Features of Microprocessor 8257 DMA Controller: The Features of Microprocessor 8257 DMA Controller are follows, 1. It is a programmable; 4-channel, direct memory access controller. Each channel can be programmed…

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8257 DMA Controller

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…

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Internal Architecture of 8275 CRT Controller

Internal Architecture of 8275 CRT Controller: The 8275 programmable CRT controller is a single-chip device that generates all the signals which are used for interfacing a microprocessor system. The main…

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Attenuator Network

Attenuator Network: An attenuator network must fulfil following conditions. It must give correct input impedance, It must give correct output impedance and It must provide specified attenuation. In general, attenuation…

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