A digital circuit that literally "counts" - it progresses through a sequence of states that are representative of some value. It need not count in a natural progression i.e. 1,2,3,4,5 etc. to be considered a counter (i.e. you can have different count sequences) each count value need not be of ...
5
votes
3answers
139 views
five month countdown timer circuit?
I'm a beginner in electronics, so I just have an idea in my head and don't know how to actually make it. I want to make a countdown circuit, for an event in next 5 month. The display format is like ...
2
votes
2answers
51 views
Easy resource to learn solving counter problems?
Could anybody please point me some direction on where I can learn to solve simple counter problems like counting in a given sequence using a given flip-flop? For example:
Create a counter counting ...
0
votes
1answer
54 views
Any Ideas for Understand one of the 3 phases has powered
I want to ask you about a situation which i couldnt find the exact solution or better way to do the job.
The situation is i have 3 phase (380V) induction motor and one of the phases to the motor had a ...
4
votes
3answers
70 views
Creating a Sequenced Array of 3 Mosfets with Adjustable Timings
I am comfortable with rudimentary 555 circuits and other basics, but I have something a little bit beyond me now.
I need to have three separate mosfets A, B, and C all turn on and off in sequence. I ...
0
votes
1answer
191 views
Can someone help check my solution for this timing diagram?
I've been working on some timing diagrams and I keep mixing up the behaviors for the different flip flops.
EDIT:
I think I have the logic correct. If someone could please let me know if I'm ...
2
votes
3answers
122 views
how to create a square wave with large duration and high duty cycle
For a "plant waterer circuit" I would like to add a safety feature that prevents watering for over ~3 minutes, and delays the next watering from occurring for ~12 hours.
Currently the circuit is ...
0
votes
1answer
472 views
3 bit synchronous counter design d flip flop
Any idea how I would go about designing a 3 bit synchronous counter in regards to having the following states
...
0
votes
1answer
44 views
Eco-roof flow meter with “counter channel” output - what is that?
Some background:
I'm working on an eco-roof flow monitoring project and we want to hook up a Unidata 6506G tipping bucket flow gauge (our effluent flow is in a strange low range range where we needed ...
0
votes
3answers
181 views
Revolutions (pulse) per minute counter circuit?
Does anyone know how to set up a circuit by using counters, decoders, 7 segment displays and a 555 timer to show the revolutions (pulses) per minute from a photo-transistor?
I'm doing this as part of ...
-4
votes
2answers
302 views
How do I build a 4-bit synchronous direct counter using only D Flip-Flops? [closed]
I have to build a counter using only D Flip-Flops and wires. What's the approach?
-1
votes
2answers
267 views
Learn CPLD from zero [closed]
a) Should I learn VHDL or Verilog? Is one excel in some area while the other better fit another area?
For simple "glue logic", says, 5 to 30 TTL chips equivalant, which is better?
b) First ...
-5
votes
1answer
285 views
Is it possible to attach PNP counter to an NPN encoder? [closed]
As a follow-up of my previous too generic question
I have a signal generator (shaft encoder) that has 2 NPN outputs.
I have a high speed counter that needs PNP signals.
How can I convert the encoder ...
1
vote
1answer
99 views
Intersection Turning Movement counts
Civil Traffic Engineers have a perpetual data gathering problem. They need intersection turning movement counts to do their studies. This has historically been a manual task. Someone sits by the ...
0
votes
1answer
116 views
How can I emulate the PS/2 protocol without a microcontroller?
I am trying to emulate the PS/2 keyboard protocol with a custom piece of hardware, without using a microcontroller. The said piece of hardware will consist of 13 momentary push buttons.
...
9
votes
4answers
422 views
Lengthening a 5 ns pulse
I have a 5 ns pulse width High coming out of a comparator that is asynchronous. I am attempting to count this pulse. My current microcontroller (dsPIC33FJ) has an asynchronous counter on board, ...
1
vote
2answers
963 views
Design a 4-bit synchronous counter using D filp-flops and 16 x 4 ROM that can generated any arbitrary counting sequence
What are the restrictions on the counting sequence? Give the ROM contents for the following sequences: a) 12, 13, 14, 15, 5, 6, 7, 0, 1, 2, 3, 4, 11, 10, 9, 8, 12, 13, etc...
b)8, 9, 0, 1, 8, 9, ...
0
votes
2answers
203 views
HEF4060B counter doesn't count
I'm building (on a breadboard) a 16Mhz oscillator (part of another circuit) with the HEF4060B using an external xtal.
Schematic I'm using is
that's not so different from the example on the ...
1
vote
2answers
313 views
Regarding Arduino Uno - Counter
I am new to Arduino so, bear with me. I am trying to make a project for a counter countdown using my Arduino Uno whereby any of the 1 out of 14 pushbutton has been pressed, it decreases a digit number ...
2
votes
1answer
325 views
VHDL - How to reduce signal's dependencies and optimize speed?
I'm wondering how to optimize comparison a wide counter value with few defined values. Maybe it will be easier if I show it on example - let say there is a receiver that gets data in well defined ...
2
votes
3answers
180 views
CPLD best practice for resetting a counter
My application has a bog-standard count-until-a-certain-number-then-reset-the-counter section. My experienced friend tells me that when using actual chips, it's common to increment the counter on the ...
0
votes
1answer
100 views
Testing a CD4018B
I would like to test a CD4018B IC.
I hooked up five LEDs to the Q1 to Q5 pins, Vdd to 5V and Vss to ground.
The five LEDs light up as soon as power is connected.
How can I advance the counter?
I put ...
1
vote
1answer
196 views
Is it possible to add a piezo buzzer to a counter
Is it possible to add a piezo buzzer to a counter:
my example:
(countD<70)
so 1 melody at =0
2nd melody 10,20,30,40,50,60
3rd melody 70
This is what I was playing around with:
...
3
votes
1answer
425 views
Unsigned addition overflow and synthesis
Let's say we have the following code where a, b and c are 3-bit wide representing unsigned ...
0
votes
1answer
244 views
2
votes
6answers
2k views
How to interface a quadrature encoder with PIC?
I'm developing a prototype that uses a quadrature encoder to measure it's linear displacement. The encoder is attached to the prototype body and has a wheel in it's shaft. As the prototype moves ...
2
votes
3answers
351 views
Using a counter to reduce pin counts for SPI slave selection
I've got five SPI SRAM chips, which I want to control off a single Arduino. I've seen setups like this, which share SCLK, MOSI ...
2
votes
1answer
145 views
An IC that would combine a counter and a decoder
I have a circuit that makes uses of a decoder to command the latch line of 8 latches.
To avoid spurious latching that could occur in transitions, I disable the decoder output while I change the input ...
1
vote
2answers
575 views
Arduino pulse counting & storing
I'm using jeenodes from jeelabs for capturing data such as temperature, light, humidity and motion. Now I am looking to capture gas and water consumption using reed switches (the meters produce x ...
3
votes
3answers
360 views
Initial or undefined value of flip flop
I am modeling Digital Circuits using ICs in a software. I have worked with flip flops and counters, but i didn't record my experience very well.
How do i model undefined or initial value of flip flop ...
-1
votes
1answer
250 views
Frustrated With D flip flop assignment
We are doing a project at school with AOI, NAND and NOR logic. The logic is used sequentially to display a number on an LED display, more specifically it is suppose to display the numbers of your ...
1
vote
1answer
801 views
Creating a one-digit scoreboard using logic circuits
I'm creating a one-digit scoreboard on a breadboard. Naturally, I have a BCD to 7-segment decoder and a 7-segment display. But I don't know how to automatically increment the display. (It's for a ...
3
votes
2answers
364 views
Issues implementing an up/down counter
I am trying to understand how to implement up/down binary ripple counter.
Basically, I have a bunch of D-flipflops, and connect clk of next flipflop to ether Q or Q'.
So, if I want to change ...
1
vote
5answers
2k views
alternative to 4017 decade counter for iterating over matrix columns
NOTE: I have made some changes since the original question, the number of columns is 114 not 45, this may affect some of the answers below.
I'm working on a project with a large LED matrix I'm ...
3
votes
1answer
433 views
4017 counter: Why do some LEDs have multiple connections in this traffic light circuit?
Schematic (from here):
Why are four legs connected to the green LED and two to the amber LED in the 4017 traffic light circuit? Shouldn't it be able to do with only one leg per LED?
3
votes
1answer
967 views
Ripple counters versus synchronous--pros, cons, and power consumption
Substantial edit--note that David Kessner's answer was written in response to the original posting; view the edit history to see what he was responding to
From what I've read of digital design, there ...
1
vote
3answers
669 views
Design 3-bit Synchronous Counter
I'm new to the whole electronic circuit scene, I've been trying to work out for hours how to design a 3-bit synchronous counter using D-Flip Flops to count in a given sequence.
So say for instances ...
3
votes
1answer
139 views
How do I determine the fastest time between pulses I can measure?
I need to calculate the elapsed time between the rising edge of one pulse to the rising edge of the next pulse. This needs to be in a mobile environment, but I am not attached to any solution as long ...
2
votes
1answer
265 views
frequency generator / counter
I want to generate a precise frequency in the 500MHz range, and have therefore purchased a VCO (200MHz to 400MHz).
To measure the VCO output frequency, I'm trying to build a high frequency counter up ...
1
vote
2answers
564 views
T-trigger: minimum transistor count
I am playing around with real implementation of basic logic schemes from transistors.
Could you suggest any compact implementations of T-trigger? Obviously, classic "CMOS" way eats way too many.
...
