hi shermaine,
the tutor's design is same with what u hav post on "Enquiry" thread.
the link is
I check the design alrdy..everything is fine.
except AND gate before the green led; tat gate is missing an input (output from JK flipflop).
and also B0 should be connected to ground also.
I edit his design with red color.
pls hav a look.
(note: u don't need to connect any unused output pin.. juz leave it unplugged.)
The explanation is
First part is
in the JK chip
The combination inputs (Ripple signal from CountUp + "A" confirm signal) are supposed to give the toggling output for 16 clk-cycle of period.
So we got the toggling signal from JK flip flop.
Second Part is
For the rest of the chips, it is easy to see tat
Since the only tsunami level 4-5 need red light, we consider implementing the period of red light out of 16 clock cycles. After the red period, the green light will be switched on by using an inverter logic gate for the rest cycles out of 16.
The Adder does the multiplying the input tsunami levels by 3. Eg. 1 -> 3, 2->6, 3->9, 4-> 12, 5->15..
U can see tat the 12 and 15 is the number wat we want red LED to be on.
In the Countdown chip (after the adder in blueprint)
The Load pin is set the starting input and the counter will count down to 0000 (which is used as feedback again to disable the chip when it reaches 0000.)
Signals below tsunami level3 are cut down by AND gate.
Finally we get the desired clk-cycle period to switch on red and green LED in desired order.
For Example, Tsunami level 4 input, we get the red light on for 12 clk-cycle period; after tat, green light will b on.
Then by combining the First part Toggling output from JK, we get the blinking red and green light.
Hopefully u will understand easily.
Actually u don't realli need ur circuit working perfectly.
If ur logic is correct, tutor will accept ur circuit design.
My one has flashing problem. but it works properly for desired period except LEDs r not blinking.
But tutor said it is quite ok as long as i can explain the circuit.
Today i finished my presentation. I had to explain the whole circuit to tutor.
U do need to understand the logic since tutor will test u with some questions differing frm our project question.
Good Luck.
Vandor
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