B. I repeat the question blogged yesterday as I still don't have a response.
What is the event in History that connects the following ?
June 27th, July 4th, Shomron, Hercules carriers, Idi Amin, Netanyahu.....
C. Now on to Embedded Systems :
Questions on oscillator section :
(You may have to do some searching to get the answers right.)
1. What type of oscillator configuration is used in the 8051 family ?
2. How many oscillator periods make one machine cycle in 8051 ? Infineon C515C ? Dallas 89C420 ?
3. When the microcontroller has a min and max frequency range and when your system can work at minimum frequency ,what frequency would you actually prefer to operate ? Min / Maximum ? Why ?
4. If we use a crystal which gives an oscillator stability of +/- 20 ppm, Calculate the likely error in one year ?
5. Compare Crystal Oscillators with Ceramic Resonators.
6. Today's C Program (Please give the detailed explanation for an answer) :
More on this tomorrow.......
ans: 0 0 0 0 0 0 0 0 0 0 0 0 1 1 1 1
ReplyDeleteexp:
sir here we are using left shift operator on i and with shift value contained in j;
so first time through the loop j=0 so in statement
i<<j++
<< has higher priority so first it is evaluated which would be 15<<0 which is 15 which is then binary anded with 0x8000 which would be
0000 0000 0000 1111
&1000 0000 0000 0000
which is 0000 0000 0000 0000 0000
so first printf will print 0.
2nd time:
j=1 and i would be now
0000 0000 0001 1110
&1000 0000 0000 0000
which is 0 again
3rd time:
j=2
0000 0000 0011 1100
1000 0000 0000 0000
which turns out to be 0
4rth time
j=3
0000 0000 0111 1000
1000 0000 0000 0000
which is again 0
5th time
0000 0000 1111 0000
1000 0000 0000 0000
which is 0
here we can observe that when we shift 4 times the lower order nibbles replace the upper order so when j=8 that is 9th time
i would be
0000 1111 0000 0000
which when anded would result in 0
and contunuing through the loop when j=12 i,e 13th time thru the loop we have
i= 1111 0000 0000 0000
anded with 1000 0000 0000 0000
so which is 1
14th time 1110 0000 0000 0000
1000 0000 0000 0000
which is 1
15th time 1100 0000 0000 0000
1000 0000 0000 0000
which is 1
16th time 1000 0000 0000 0000
1000 0000 0000 0000 which is 1
hence the o/p
1.A) Crystal osillator configuration is used in 8051 family.It is also known as Pierce oscillator.
ReplyDelete2.A) 8051=12 oscillator periods,Infineon C515C=6 oscillator periods,Dallas 89C420=1 oscillator period.
3.A) One should choose lowest possible oscillator i.e. min frequency which will be compatible with our application.As performance will increase.
4.A) Nearly 10 minutes(Gain or Lose) for +/-20PPm(parts per million).Because there are 32 million seconds in a year.Thus 30*20 seconds=600 seconds=10 minutes.
5.A) Advantages of Ceramic Resonators over crystal oscillators:small size,cheaper.
Disadvantages of Ceramic Resonators over crystal oscillators:Low stability(nearly +/-4000).
As coming to 6 one Mr.Manoj had already given the answer and he is absolutely right according to my knowledge.
In the question
printf("%d",(i<<j++ & 0x8000)?1;0)
is suppose to be
printf("%d",(i<<j++ & 0x8000)?1:0)/*Please note colon instead of semicolon*/
Happy to see Manoj back again !
ReplyDeleteSoumen's answers are all correct. I want all students to dig deeper into the concepts and answer like Soumen does.
I have corrected the typo pointed out by Soumen.
Thanks all
B)
ReplyDeleteSir,
Is it the operation Entebbe in Uganda which connects June 27th, July 4th, Shomron, Hercules carriers, Idi Amin, Netanyahu.
The Bicentennial Operation Sail celebration was also held in New York Harbor on July 4th,1976.
Bharat
ReplyDeleteWell done, you are correct. The event was the raid on Entebbe. Those interested can get all the information on the net.
Let us share this memorable event on July 4th.
the question about entebbe operation, the c program question & the oscillator questions are all answered ....before i could see them...as my internet connection was bad for a few days...
ReplyDeleteany way..the answer for the question A (photograph)hasn't been answered...so i think they are the
"george.w.bush & the famous lance armstrong"
altough the picture is quite hard to recognise...i've instantly recognised it...as the pic taken at crawford ranch, texas...!!
how 2 post the answers
ReplyDeleteElectron,
ReplyDeleteI must say you answered a very difficult question - identifying the people in the picture. This is one question for which you either know or you dont know the answer.
Happy that you got it right.
Bush was finally ambushed by an electron !
You have already posted one !
ReplyDeleteSeriously, anyone (including anonymous) are permitted to post. No restrictions.
To avoid spam, word verification step is included. That is all.