here are some of the job interview questions.
:?:implement an ex-nor gate using ex-or gates only
:?:implement a NAND-gate using a single module of 2:1 mux only. dont use any combi. modules.
l:?t of questions on hold and settling time like: what happends to the output of a D FF if the data changes a)with in the settling time. b) within the hold time.
:?:what are the advantages of mealy and moore machines.
if you know the answers, please do post to this forum.
hi,
i agree with the answers...if in the second case, u think Bbar can't be given as such, u can use a mux to invert b..for that, give ' 1'(VDD) and '0'(GND) as the input to 0 & 1 pin of the MUX...now give b as the selection line..now when b is '1', then '0' is sent out otherwise '1'........
if set up time and hold time were not met, then the output would be in -determinate state.....
mealy machine is used where we need fast circuit design and where little glith probelms doesnt matter becoz we do not register the output of mealy data and it can some times called as asyn type state machine as it doesnt care about the clock edge where it cares about the present input and present state change.
where as moore machine the output is always registered so atleast one clock cycle data output delay will be there. where timing critical applications are there we go for moore based state machine design
if i am wrong plz correct me......................
It depends on your requirement. for ex. if you want to detect a pattern and generate output while detecting the last bit of the particular pattern(no delay), mealy FSM will be more useful.