I have had a few people involved in trying to create a USB I/O board that receives a 10V input signal to trigger a usb output that communicates with a web page to print a label in a manufacturing environment. The issue I am having is I do not know what to order that will allow me to make it all work. I have a decent size budget and am hoping to find a solution soon. Any help on this matter would be appreciated. Any ideas?
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You could "abuse" a cheap USB mouse.
Replace one of the mouse buttons by a photocoupler (the transistor side).
Connect the LED side of the photocoupler via a series resistor to the 10 V input.
In the PC program check for the corresponsing mouse click (left, right , middle depending on which mouse button you manipulate) and start printing.
If your program haas a "print" button, the easiest way is to replace the left mouse buttonm by that contraption, place the cursor manually over the "print" button and have the 10 V input issue left mouse clicks.
Harald
Replace one of the mouse buttons by a photocoupler (the transistor side).
Connect the LED side of the photocoupler via a series resistor to the 10 V input.
In the PC program check for the corresponsing mouse click (left, right , middle depending on which mouse button you manipulate) and start printing.
If your program haas a "print" button, the easiest way is to replace the left mouse buttonm by that contraption, place the cursor manually over the "print" button and have the 10 V input issue left mouse clicks.
Harald
Thanks for the input Harald
I like the idea. The only issue I am having is I already have an input signal that is 10v coming from a manufacturing machine that tells the label when to print. I guess my big issue is finding a USB I/O dongle possibly that I can program an input to emulate the enter key on a keyboard. I am just not familiar enough with USB I/O dongles and what software is available to program the inputs?
I like the idea. The only issue I am having is I already have an input signal that is 10v coming from a manufacturing machine that tells the label when to print. I guess my big issue is finding a USB I/O dongle possibly that I can program an input to emulate the enter key on a keyboard. I am just not familiar enough with USB I/O dongles and what software is available to program the inputs?
However I failed to mention that the current setup is a small number keypad that I use and a machine operator pushes the enter key when they are ready to get their label. I could possibly "abuse" the little usb keypad but can I use a photo coupler for something like that? Would that work?
Using an optocoupler with the transistor output connected in parallel with the 'Enter' key, and a resistor in series with the 10V input should do the trick.
Just take care with the polarity of both signals.
TOK
Using an optocoupler with the transistor output connected in parallel with the 'Enter' key, and a resistor in series with the 10V input should do the trick.
Just take care with the polarity of both signals.
TOK
I think I can go with your option
Here is an image of the board with the enter button placement. Can you give me any more direction on what optocoupler and resistor would work for this project? I am new to this so I don't want to trash a very expensive computer because I didn't get the signals right.
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I recommend not to use a mechanical relay. Those tend to bounce which will give multiple input signals to the keyboard.
Use something like a Photomos relay: http://pewa.panasonic.com/assets/pcsd/catalog/aqy-dip-form-a-catalog.pdf (Photomos is a panasonic trademark - I'm in no ways associated with panasonic. There are similar components from other manufacturers, too). The advantage over a photocoupler is that a photmos relay is bidirectional.
The picture looks a bit odd: are there 3 ENTER keys, or is the ENTER key just so big that it covers 3 contacts? I assume the latter, since all 3 marked contacts are in parallel. Connect the output of the photomos relay across one contact (left-right in the picture you showed us). Add a series resistor of R=(10 V - 1.5 V)/10 mA ~ 1kOhm to the LED side of the photomos relay.
Observe the correct polarity for the LED! If you want to make the circuit fool-proof, add a bridge rectifier in front of the LED-Resistor circuit. Make the AC-side of the rectifier the 10 V input from your source, connect the DC side of the rectifier to the resistor and LED. Make the resistor 750 Ohm for this setup because some voltage drops across the brifge rectfier.
Regards,
Harald
Use something like a Photomos relay: http://pewa.panasonic.com/assets/pcsd/catalog/aqy-dip-form-a-catalog.pdf (Photomos is a panasonic trademark - I'm in no ways associated with panasonic. There are similar components from other manufacturers, too). The advantage over a photocoupler is that a photmos relay is bidirectional.
The picture looks a bit odd: are there 3 ENTER keys, or is the ENTER key just so big that it covers 3 contacts? I assume the latter, since all 3 marked contacts are in parallel. Connect the output of the photomos relay across one contact (left-right in the picture you showed us). Add a series resistor of R=(10 V - 1.5 V)/10 mA ~ 1kOhm to the LED side of the photomos relay.
Observe the correct polarity for the LED! If you want to make the circuit fool-proof, add a bridge rectifier in front of the LED-Resistor circuit. Make the AC-side of the rectifier the 10 V input from your source, connect the DC side of the rectifier to the resistor and LED. Make the resistor 750 Ohm for this setup because some voltage drops across the brifge rectfier.
Regards,
Harald
You are correct there is three points of contact for one button. I appreciate the help. It will certainly make this a lot easier to accomplish!
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