Digital Logic and Microprocessors

Here, the output is high only when both the inputs are low.

This instruction allows the programmer to match the byte in the accumulator with a fixed mask byte, contained in the second byte of the instruction in 8085 processor.

These instructions provide  means of subtracting a fixed value from the contents of the accumulator in 8085 processor.

It is a device that allows digital information from several sources to be routed onto a single output line for transmission over to a common destination.

It accepts an active level on two more of its inputs representing digit, such as decimal or octal and converts it to a coded output such as binary or BCD.

J = 0, K = 1 is a command to reset the flip-flop.

The simplest half-adder design, pictured on the right, incorporates an XOR gate for S and an AND gate for C. With the addition of an OR gate to combine their carry outputs, two half adders can be combined to make a full adder.

This I/O mode in 8255 allows handshake signals to exchange between the microprocessor and peripherals prior to data transfer.

DAA stands for Decimal Adjust AL after addition. This arithmetic instruction in 8086 is used to make sure that the result of adding two packed BCD numbers is adjusted to be a valid BCD number.

These ports in 8255 microprocessor are basically bidirectional I/O pins that act as latched outputs or buffered inputs depending upon the control word loaded into the control word register.

AND gate having 2 input has 4 input in truth table. AND gate having 3 input has 8 input in truth table. AND gate having 4 input has 16 input in truth table. AND gate having 5 input has 32 input in truth table. AND gate having 6 input has 64 input in truth table. AND gate having 7 input has 128 input in truth table.

This flag bit supported by the 8085 CPU is set when the result of ALU operation is zero.

DMA controller uses the registers to store the starting address, word count and the status of the operation. Option (2) is true.

This register contains the result of arithmetic and logical operation.

Here, all the major calculations take place in EAX making it similar to a dedicated intex86 accumulator register.