ladydarkness
November 24th, 2006, 01:36 PM
Alright well this isn't for exams or anything I need help with my project... I'm in grade 12 but this is a grade 11 course and since most of you have way more experance than me perhaps you can help
I need to draw a diagram, I know what I'm talking about and I know how everything works but when it comes to putting it on paper my brain seems to sizzle and fry..... well here is the project..
A three car race track has sensors in each lane at the finish line. As the cars cross the finish line their respective sensors respond and send a signal to a digital circut. The three "finish" signals occur in the same order that the cars finish in. The digital circut has a 3x3 matrix of nine LED's which indicate the placement of each car.
You're hired by the race track committee to design and build a digital circut that will operate as described above.
The LED indicators must be laid out as shown on the picture.
A push button resets the circut and extinguishes all lit LED's.
Design Hints:
*The signals from the track sensors are 10mS HIGH pulses. One pulse per race.
*Each LED is lit by an R.S. flip-flop.
*A two bit binary counter will start at zero and be incremented every time any track pulse occurs.
*Gating circuts are advised
*remember, each track signal only appears for every race
http://img62.imageshack.us/img62/9506/racetrackproblemlz8.jpg
Now what I figured out is:
I'm going to need 3 monostable multivibrators (one-shot multivibrators), 9 7474 (dual D flip-flop - positive edge triggered with preset and clear) RS-flip flops for each LED, and 7476 (dual j-k flip-flop with preset and clear)
also, the counter will count from 0 to 2 and will then be reseted and this will
also reset RS filpflop and hence my LED.
Let me name First postion in track A as A1, sceond position as A2 and
so on. 10mS high pulse for track A be denoted by signal A_HP.
Suppose A_HP goes high => some car completed track A. Glowing of which
LED in A will depend upon the state of LED of track B & C.
also i have to understand how the chips work well what i know is with the astable multivibrator (clock, free running) gives outputs continuous stream of pulses
Also my teacher was going on about a circut signal "race" condition.. I dident understand a lot of that except It exists when an active signal needs to activate 2 or more other ccts. A "race" condition must be avoided apperantly so he says...
sigh thats all I can really think of right now...
But please I really need help on this circut drawing
I need to draw a diagram, I know what I'm talking about and I know how everything works but when it comes to putting it on paper my brain seems to sizzle and fry..... well here is the project..
A three car race track has sensors in each lane at the finish line. As the cars cross the finish line their respective sensors respond and send a signal to a digital circut. The three "finish" signals occur in the same order that the cars finish in. The digital circut has a 3x3 matrix of nine LED's which indicate the placement of each car.
You're hired by the race track committee to design and build a digital circut that will operate as described above.
The LED indicators must be laid out as shown on the picture.
A push button resets the circut and extinguishes all lit LED's.
Design Hints:
*The signals from the track sensors are 10mS HIGH pulses. One pulse per race.
*Each LED is lit by an R.S. flip-flop.
*A two bit binary counter will start at zero and be incremented every time any track pulse occurs.
*Gating circuts are advised
*remember, each track signal only appears for every race
http://img62.imageshack.us/img62/9506/racetrackproblemlz8.jpg
Now what I figured out is:
I'm going to need 3 monostable multivibrators (one-shot multivibrators), 9 7474 (dual D flip-flop - positive edge triggered with preset and clear) RS-flip flops for each LED, and 7476 (dual j-k flip-flop with preset and clear)
also, the counter will count from 0 to 2 and will then be reseted and this will
also reset RS filpflop and hence my LED.
Let me name First postion in track A as A1, sceond position as A2 and
so on. 10mS high pulse for track A be denoted by signal A_HP.
Suppose A_HP goes high => some car completed track A. Glowing of which
LED in A will depend upon the state of LED of track B & C.
also i have to understand how the chips work well what i know is with the astable multivibrator (clock, free running) gives outputs continuous stream of pulses
Also my teacher was going on about a circut signal "race" condition.. I dident understand a lot of that except It exists when an active signal needs to activate 2 or more other ccts. A "race" condition must be avoided apperantly so he says...
sigh thats all I can really think of right now...
But please I really need help on this circut drawing
