Question { 25294 }

What is flag, bus?

Answer

Flag is an eight bit register which shows the status of
results store in accumulator,after executing an
instruction.There are 5 flag in 8085 microprocessor,
Sign:States whether the result is +ve or -ve.
Zero:set when result is zero,otherwise reset.
Parity:Set for even parity,otherwise reset.
Carry:Set if there is an end carry.
AC:Set if carry generated by leftmost nibble.


Bus is a interconnecting device through which data
transfer is occur.

Question { 155324 }

What is ALE? Explain the functions of ALE in 8085.

Answer

ALE is a control signal of 8085 MPU.8085 is a 8-bit
microprocessor which have 16-bit address bus among them
lower 8-bit are multiplexed.So while MPU executes read or
write operation it needs to demultiplexed.ALE control signal
used to demultiplexed the lower order address and data bus.