USART 8251 (Universal Synchronous/ Asynchronous Receiver Transmitter)

USART 8251 (Universal Synchronous/ Asynchronous Receiver Transmitter) 1. Draw the pin diagram of USART 8251. Ans. The pin diagram of 8251 is as shown below: 2. Draw the functional block diagram of 8251. Ans. The functional block diagram of 8251 is shown below: 3. How many different sections does 8251 have? Ans. 8251 has five […]
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BUS STANDARDS RS:232C Standard

BUS STANDARDS RS:232C Standard 1. What logic convention is followed in RS-232C and indicate the corresponding voltage levels also. Ans. A negative logic convention is used for such a standard. Logical ‘1’ is represented by a transmitted voltage level in the range of –3V to –15V, while a logical ‘0’ is represented by a transmitted […]
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Programmable DMA Controller (DMAC) 8257

Programmable DMA Controller (DMAC) 8257 1. Draw the pin diagram of8257. Ans. The following figure gives the pin connection diagram of 8257. 2. Draw the functional block diagram of8257. Ans. The following figure shows the functional block diagram of the DMAC 8257. As is apparent from the figure, it consists of eight blocks: data bus […]
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Priority Interrupt Controller 8259

Priority Interrupt Controller 8259 1. Draw the pin diagram of PIC 8259. Ans. The following shows the pin details of PIC 8259.     2. Draw the functional block diagram of PIC 8259. Ans. The following shows the functional block diagram of 8259. 3. Draw the block schematic showing the interconnections between several I/O devices […]
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