Electronic Circuits Projects Diagrams Free - Homework Help

8051 assember help

fkuk — Fri, 20 Nov 2009 20:48:12 GMT

hi

i have this assignment that i have to do and what i need to do is create a 8051 assembler program
basicly convert binary to show decimal numbers on a 7 segment display
the binary numbers are input using switches on a project board and i need to program a ats8something

all i want to know is the steps i need to do to make this happen i probaly be able to program it
something like a flowchart would be helpful

thanks

Motion detector connect to RS232

talar_bdg — Mon, 16 Nov 2009 20:08:23 GMT

Hi. Im new on this forum and i dunno english so well so sorry for few language mistakes!
I have a work to do. I need to connect motion detector to a computer. I want to do this by RS232. From detector are two signal outputs, so i connect it to pins number 4 and 7 (RTS and DTR). It is right?? How to test this connection??

In next step on my work, i have to write program (in C++). For begining, when detector detect a motion on the screen will appear a message like "Attention, motion detect".

Can somebody help me??:>

op amp question

ahivarn — Sun, 15 Nov 2009 17:26:28 GMT

calculate full power bandwidth for amplifier using ic741 OP AMP if Voutput is 5 volts peak to peak.
plz help

TDM Signal

samina — Sat, 14 Nov 2009 12:54:00 GMT

can anyone tell me a site address for digital representation, block diagram for TDM signal.. its urgent . please help

samina

Exam revision, no solutions to check answers against.

Macka — Sat, 14 Nov 2009 07:50:20 GMT

Hi Everyone,

I am currently studying for an exam (on semi conductors) and have come across a question that I can not complete, nor do I know if what I have done so far is correct.

The lecturer will not give us solutions for tutorial questions or past exams, so I have no way of checking my answers. Many of the exam questions are taken from our text book, however this one does not appear to have come from there.

Quote:

What is the power dissipation in the zener diode (Vzener = 15V, rz=0) in this circuit for:
a) RL = ∞
b) RL = 75 Ω
c) RL = 50 Ω

My solutions:
a) RL = ∞ = open circuit
so V(150Ω) = 50 -15 = 35V
Id = 35/150Ω = 200mA
P = VI = 35V*200mA = 3.5W

b)
Approach 1:
It = I total
I2 = current through RL

L1: 50V = It*150Ω + 15V
L2: 50V = It*150Ω + I2*75Ω
It*150Ω + 15V = It*150Ω + I2*75Ω
15V = I2*75Ω
I2 = 15/75 = 1/5 = 200mA Alarm bells! surely this can't be right?

Approach 2:
V2 = Vt*(rz//RL) / (150Ω + (rz//RL)) Voltage divider rule
15V = 50V*(rz//75Ω) / (150Ω + (rz//75Ω))
50*(rz//75Ω) = 2250 +15*(rz//75Ω)
35(rz//75Ω) = 2250
(rz//75Ω) = 64.28
rz = 0.0155 Alarm bells! surely this can't be right? rz should be 0 :mad:

c)

Same as b).

I am completely lost, a prod in the right direction would be much appreciated.

Attached Thumbnails

rc helicopter control loop

tomas632 — Thu, 12 Nov 2009 19:31:12 GMT

hi guys,

i currently have a project where i have been asked to take an off the shelf rc helicopter and re-program it to make it autonomous so that it takes off and flies a pre-designated path. I am extremely stuck on how to go about doing this from a control point of view and we have been given no assistance with this project.

I was thinking that I could model each of the motors and calculate a relationship between applied voltage and motor speed, but if each of the rotors are not identical they may not create the same lift as one another.

Another idea was to use accelerometers to measure the angle the heli was at and correct by slowing down/speeding up individual motors according to the direction of pitch. could anyone offer any suggestions?

Also in terms of the controller would a PID controller be suitable or would a different type be better? I'd really appreciate any help.
cheers

Tom

non quantization,ISI,transmission path

samina — Thu, 12 Nov 2009 13:23:01 GMT

can any one explain me the following topics plis-

non quantization,ISI,transmission path,

Power of error and Parseval's theorem

Emil09 — Thu, 12 Nov 2009 10:35:17 GMT

I'm approximating a square wave using a Fourier series. I need to determine the power of error by using Parseval's theorem. The problem is that I don't understand the connection between power of error and Parseval's theorem. Can anyone explain this?

BTW, here is a graph of what I'm doing (in Maple).

please help here!

melvinspeed21 — Tue, 10 Nov 2009 14:54:22 GMT

please help me, I have 2 transistor mutivibrator circuit and I really need help to have how does each its components works in circuit, specially the transistor on how can it output an alternating light. please help me! thanks! :

http://www.talkingelectronics.com/Fr...ts/Page16.html

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graphical representation of generation of Pulse modulation

samina — Tue, 10 Nov 2009 11:36:41 GMT

can anyone provide me graphical representation of generation and de generation of Pulse modulation?

Three phase full wave bridge rectifier

cj62565 — Mon, 09 Nov 2009 23:40:53 GMT

Hi,
I was asked in school, if I have 480vac going in and 630vdc coming out, how would I come up with this dc figure. I was not given any other values, and I'm comoing up with around 678vdc. There would be some voltage drop associated with the diodes but that is minimal. Around 4.2v. So I know thats not the reason for the drop of around 48v. This is not a test or homework, but just something my instructor asked at the end of class.

CJ

fourier transform homework

tau17 — Sat, 07 Nov 2009 15:53:24 GMT

hi
this is a question from a book but it seems a strange one it says for the following prove that the inverse fourier transform is complex and the real n imaginary parts are a hilbert pair.

a) G(f)=1/2 at f=0
b) G(f)=0 for f<0

the way i see it it is 1/2delta(f) at f=0 and that should inverse transform to 1/2 and that is real or am i supposed to take it as 1/2+0j and take fourier transform of 1/2 that is half delta and that multiplied by -jsgn(f) would lose the dc value so its inverse would be 0 as hilbert removes dc component
and i dunno what to do about (b)
can some one please help

speaker

bashekmagroh — Sat, 07 Nov 2009 02:44:02 GMT

hi guys ..
can we replace the 16 ohm speaker with 8 ohm ??
am using the Isd 1110 voice recorder IC

biasing of an op amp

samina — Wed, 04 Nov 2009 14:35:54 GMT

can any one please tell me how a voltage divider provide biasing for an op amp.especially when both inputs are connected to a common dc source.
plis plis help me.........

7 segment

hbkwant — Tue, 03 Nov 2009 15:05:13 GMT

Design a seven segment display which displays �INDIA IS GREAT �with certain delay (say 5 sec) between successive letter displays in continuously and decoding circuitry must be combinational circuit and OPTIMAL