8051 MICROCONTROLLER
ARCHITECTURE OF 8085
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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EA
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ALE
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Vcc
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RESET
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Detailed explanation-1: -Pin 9 (RST): It is a reset input Pin, which is used to reset the 8051 microcontrollers to their initial values when logic 1 is applied to this pin. It is an active high pin.
Detailed explanation-2: -Detailed Solution. In the 8051 microcontrollers the control line External Access or EA line is used to read data from both internal and external memories, first internal then external is read. In question 8051 is reset and the EA line is set to HIGH (logic 1) then the first program read is internal code memory.
Detailed explanation-3: -RESET CIRCUIT OF 8051 CONTROLLER RESET is an active High input When RESET is set to High, 8051 goes back to the power on state. The 8051 is reset by holding the RST high for at least two machine cycles and then returning it low.
Detailed explanation-4: -When the 8051 is connected to an external memory, it provides path for upper 8-bits of 16-bits address, and it cannot be used as I/O. Upon reset, Port 2 is configured as an input port. The following code can be used to send alternating values of 55H and AAH to port 2.