help needed with a counter

[swede0418]

hello, i would like to first introduce myself. my name is Tom, i am trying to perfect my fishing reel i recently invented a little over a year ago. i love to learn about electronics and this simple project is making me crazy. i would hope that someone could shed some light on my issue. i recently decided to install a simple digital counter to my fishing reels to display the amount of line that is out. my hope is to build an inexpensive counter that will add, subtract sense direction and reset to zero with a press of a button. the counter needs to count at speeds of 1000 rpm's. also i would like to count 1 time per 2 revolutions. so basically i found this trumeter 7000as i would like to work with except i can't figure out what i need to do to get it to sense direction. i can get it to add using a magnet and a hall effect sensor, but it adds turning in both directions. i would like to work with this counter display, unless you have a better one to suggest. i like this counter because the company is in my back yard. if any one could help me solve this issue i would greatly appreciate it.

thanks

Tom



 

[swede0418]

i forgot to mention that if it counts at 1 count per revolution that would be ok too.

 

[cubeusk]

Direction sense is done through pin 2. If you want to add you have to apply a logic 1 (that is your V+). But if you want to subtract you have to apply a logic 0 (that is 0V). Now I hope your issue is solved. But if not, let me know.

 

[swede0418]

Direction sense is done through pin 2. If you want to add you have to apply a logic 1 (that is your V+). But if you want to subtract you have to apply a logic 0 (that is 0V). Now I hope your issue is solved. But if not, let me know.

thanks for the reply. i guess i need help with the sensor type and how to wire it. i do not understand the meaning of logic 0 and logic 1. i used a hall effect sensor to trigger the count up. but can i use a hall effect sensor to detect the direction? if so do i just wire it the opposite way? if you could help me with that it would be a great help.

Thanks

Tom

 

[cubeusk]

If this is you issue then post what hall sensor you want to use (the model or the datasheet). Logic 0 is 0V and logic 1 is V+ of the 7000as.
Have you think about using encoders? You could use a differential encoder.

 

[swede0418]

If this is you issue then post what hall sensor you want to use (the model or the datasheet). Logic 0 is 0V and logic 1 is V+ of the 7000as.
Have you think about using encoders? You could use a differential encoder.

yes i did look into encoders but as i found out, the encoder sends pulse signals at more than 1 per rotation. since it pulses more than 1 it will count multiple counts per 1 revolution. there is no adjustment on the 7000as to do the math, so the encoder is out of the question in my opinion unless you can tell me how to make it count 1 count per 1 revolution... as for the hall effect sensor i am currently using
ATS177-PG-A-BDICT-ND
IC HALL SENSOR LATCH 25MA SIP-3L
HTSUS: 8542.39.0000 ECCN: EAR99
LEAD: LEAD FREE ROHS: ROHS COMP
COUNTRY/ORIGIN: TAIWAN
CAGE: 12060

thanks for the reply

Tom

 

[cubeusk]

Is impossible to sense the direction with that hall effect latched sensor. Since is latched only the presence of the magnetic element is detected but the approaching side. You may sense it with two of these sensor, detecting which is the first changing his state.

 

[swede0418]

can someone help me with the part number of the sensor you suggest with a wiring diagram on how you think in should be wired? i never figured this would be so hard. the company that makes the displays is about useless. i would even be willing to pay someone to get it to work if any one is interested.

Thanks

Tom

 

[rohitkhanna]

T7000as ... nice product, and very intuitive & simple interface. Good choice. How much does it cost btw ?

But clearly the trouble you are facing requires a creative & elegant/ fairly failsafe solution. Which should work at almost any speed of reel-out/ reel-in.
Let me see what I can think of.. give me a little time.

cheers!

 

[swede0418]

T7000as ... nice product, and very intuitive & simple interface. Good choice. How much does it cost btw ?

But clearly the trouble you are facing requires a creative & elegant/ fairly failsafe solution. Which should work at almost any speed of reel-out/ reel-in.
Let me see what I can think of.. give me a little time.

cheers!

that would be wonderful. so far the company gave me 6 demo units to play with all different models. there support is not great to say the least. they tell me they cost around $20.00 each for the 7000as but if you order quantity they will reduce the price. as far as coming up wit a complete working unit i am having troubles. to be honest with you and the rest of the people looking, i do not have the experience with making all the proper circuits. so if you could please explain the small circuits as far as what they are and possibly a part number that would be a great help. i do know that the symbols represent a part but i don't know them. thanks for all you help trying to help me as well. i attached a photo of my reels to give you an idea of what i created.

---------- Post added at 13:26 ---------- Previous post was at 13:24 ----------



---------- Post added at 14:08 ---------- Previous post was at 13:26 ----------

can you explain what the other parts are? i don't know what the other circuits are....thanks again for your help.

Tom

 

[rohitkhanna]

LoL !! nice pic. Now you're just showing off... is that a Marlin ?!??!

Ok here's the thing. Concept to start with --

Your fundamental problem is determining direction. The actual number of revolutions is easy.
So here's what is possible.

You need 2 hall sensors and 2 small magnets.
Place the hall sensors approx 90^o apart on a circle, and the magnets approx 180^o apart on the same circle.

The sensors should be fixed, since they will have wires going to them, but the magnets can be attached to your reel so that they rotate with it. Attach them so that they at one facing North out, and one facing South out.

Both the Hall sensors should be facing the same way. BTW these sensors need to be the "switching" kinds, not the "linear magnetic" sorts. AH1751 is one such which can be obtained from Digikey for around $0.30 in small quantities.

Okay... now we need to add a D-Flip Flop.

All you need to do is feed the outputs of one sensor (they will need a resistor connected to +V battery) to the "D" input, and the other sensor to the "Clock" input.
The output of the D-FF will be a signal which tells you the direction. Connect that to your 7000as Direction input.
(note that a D-FF has 2 outputs which are opposite of each other. If the direction turns out to be wrong, just flip to the other output).

Now connect either one of the hall-sensors ALSO to the Count input of the 7000as.

But here's the nice part.... These D-FF's come in pairs in that chip. Since you want 1 count per 2 revs, you can use that 2nd DFF to DIVIDE your count value by 2 !! Very standard concept for a D-FF. You can divide the Hall output BEFORE you connect to the 7000as Count input and get EXACTLY what you want.

I believe the total cost of this whole thing would be under $2.. excluding you battery/ power source.

Want a complete component's & circuit diagram ?

 

[swede0418]

you are the best, if you can send a diagram that would be awesome. you do not have any idea how much this means to me. thanks a million....you explained it perfectly i understand 100%. oh if your in the fort lauderdale area i will hook you up with fish or fishing, and that was a swordfish.

Tom

LoL !! nice pic. Now you're just showing off... is that a Marlin ?!??!

Ok here's the thing. Concept to start with --

Your fundamental problem is determining direction. The actual number of revolutions is easy.
So here's what is possible.

You need 2 hall sensors and 2 small magnets.
Place the hall sensors approx 90^o apart on a circle, and the magnets approx 180^o apart on the same circle.

The sensors should be fixed, since they will have wires going to them, but the magnets can be attached to your reel so that they rotate with it. Attach them so that they at one facing North out, and one facing South out.

Both the Hall sensors should be facing the same way. BTW these sensors need to be the "switching" kinds, not the "linear magnetic" sorts. AH1751 is one such which can be obtained from Digikey for around $0.30 in small quantities.

Okay... now we need to add a D-Flip Flop.

All you need to do is feed the outputs of one sensor (they will need a resistor connected to +V battery) to the "D" input, and the other sensor to the "Clock" input.
The output of the D-FF will be a signal which tells you the direction. Connect that to your 7000as Direction input.
(note that a D-FF has 2 outputs which are opposite of each other. If the direction turns out to be wrong, just flip to the other output).

Now connect either one of the hall-sensors ALSO to the Count input of the 7000as.

But here's the nice part.... These D-FF's come in pairs in that chip. Since you want 1 count per 2 revs, you can use that 2nd DFF to DIVIDE your count value by 2 !! Very standard concept for a D-FF. You can divide the Hall output BEFORE you connect to the 7000as Count input and get EXACTLY what you want.

I believe the total cost of this whole thing would be under $2.. excluding you battery/ power source.

Want a complete component's & circuit diagram ?

 

[rohitkhanna]

Thanks dude.. but not close to Ft L. I'm about 12 time zones away

Ok.. here's the circuit. Needs to be connected up the way I explained above. I am quite sure it will work, though I have not actually tested it out or anything.
It will work for extremely high speeds & extremely low speeds equally well.





The voltage is given as +5v, which is sometimes a challenge for simple circuits. I could suggest an alternate part number for a variable voltage .. something like CD4013 maybe. What power are you expecting to use ? Dry cells ? We would need to adjust a bit for that.

cheers!

 

[swede0418]

thanks a lot,

i would like it to be all self contained. i planned on using a 9v battery with a small voltage reg. do you think that will do the trick for power? any suggestion on this as well would be great.

---------- Post added at 16:19 ---------- Previous post was at 15:56 ----------

few last questions, what resistors do i use a standard 10k? and what are the connections 7 and 14 going to? if i wire it up exactly the way you have it in the diagram it will count 1 count for every 2 rotations? if it does that, you are the man. i owe you big time.......other than that i think i got it.

Tom

Thanks dude.. but not close to Ft L. I'm about 12 time zones away

Ok.. here's the circuit. Needs to be connected up the way I explained above. I am quite sure it will work, though I have not actually tested it out or anything.
It will work for extremely high speeds & extremely low speeds equally well.





The voltage is given as +5v, which is sometimes a challenge for simple circuits. I could suggest an alternate part number for a variable voltage .. something like CD4013 maybe. What power are you expecting to use ? Dry cells ? We would need to adjust a bit for that.

cheers!

 

[rohitkhanna]

7 & 14 are the pin numbers of the D-FF power supply pins. For 9-v operation the Hall sensor I mentioned will work fine, but you will need to use a 4000 series D-FF. HEF4013 comes to mind. The pin numbers for that are different, so beware & make mods accordingly.
10k pullups should do fine. Almost any resistor should be ok within around 2.2K upto 47Kohm.

However I notice that your 7000as needs a lower voltage ~ 3.4v max. You'll need a regulator for that. The current mentioned is quite low ( is it an LCD display ? has to be at that current). So a simple 3.3v Zener diode with series resistor should be okay there.

It'll work you're on your way.

cheers!

 

[swede0418]

awesome, thanks for all your support.........there are wonderful people out there.....lol

thanks again,

Tom