Turn 12v engine on/off from a PC

[Luis]

I need to turn a 12V engine on and off from a computer program running
in a PC and at the same time use a set of IR emitter and receiver to
know to know if a sheet of paper is between the two.
Can someone suggest a part list and schematic including the wiring to
a standard port (serial, parallel or USB).
Pointers to similar projects are welcome.

The engine control and the sensor are independent, the program running
in the PC will provide have all the logic.
I have a very basic knowledge of electronics but I know how to
read/write to the PC ports.

Thanks in advance

 

[Lord Garth]

I need to turn a 12V engine on and off from a computer program running
in a PC and at the same time use a set of IR emitter and receiver to
know to know if a sheet of paper is between the two.
Can someone suggest a part list and schematic including the wiring to
a standard port (serial, parallel or USB).
Pointers to similar projects are welcome.

The engine control and the sensor are independent, the program running
in the PC will provide have all the logic.
I have a very basic knowledge of electronics but I know how to
read/write to the PC ports.

Thanks in advance

You could open and old mouse and use its optical interrupters and
interface circuitry for your slot sensor. As for the 12 volt motor,
what sort of current does it require?

 

[Robert Monsen]

I need to turn a 12V engine on and off from a computer program running
in a PC and at the same time use a set of IR emitter and receiver to
know to know if a sheet of paper is between the two.
Can someone suggest a part list and schematic including the wiring to
a standard port (serial, parallel or USB).
Pointers to similar projects are welcome.

The engine control and the sensor are independent, the program running
in the PC will provide have all the logic.
I have a very basic knowledge of electronics but I know how to
read/write to the PC ports.

Thanks in advance

I hacked this up for you:

http://home.comcast.net/~rcmonsen/ppmotoron/ppmotoron.html

Remember, NEVER CONNECT THE PARALLEL PORT GROUND TO YOUR MOTOR GROUND!
You'll trash your PC with huge inductive spikes. Use optoisolators only.

In addition, I used an OPB680 rather than a normal slot interrupter because
IR can apparently see through some kinds of paper. You might not want that.
The OPB680 has a little plastic door that can get pushed by a piece of paper
without bending the paper. Using something else should work, just check the
current requirements.

http://www.optekinc.com/pdf/OPB680.pdf

If you could post your program on how to control the parallel port (on
alt.binaries.schematics.electronic please) I'd be indebted. Pesky Windows
PCs aren't nearly as friendly to program as a nice MIPS core... no branch
delay slot? You gotta be kidding...

Or you could email it to me at rcmonsen hat comcast dot net.

Regards,
Bob Monsen

 

[Luis]

You could open and old mouse and use its optical interrupters and
interface circuitry for your slot sensor. As for the 12 volt motor,
what sort of current does it require?

I have open my mouse and realized the paper is transparent to IR, I
only got a reaction in the mouse pointer when I use plastic or metal.
Do you know how can I tune the sensibility of the interruptor?

I was going to use a cheap ac-adapter with 12v motor I have somewhere.
But because I will use a very slow gear I'm also considering using a
3v walkman motor.(the paper sheets are small and thin)

thanks again.

 

[Lord Garth]

I have open my mouse and realized the paper is transparent to IR, I
only got a reaction in the mouse pointer when I use plastic or metal.
Do you know how can I tune the sensibility of the interruptor?

I was going to use a cheap ac-adapter with 12v motor I have somewhere.
But because I will use a very slow gear I'm also considering using a
3v walkman motor.(the paper sheets are small and thin)

thanks again.

You might need to reduce the current to the Ir emitter using a resistor.
I can't tell you the value, you'll just need to experiment. The reduced
intensity may do the trick but if not, you may need to build your own
using a visible LED and a photo transistor. Very likely you can remove
the optical interupter from the mouse and bring the connections out a short
distance to accomplish this.

As for the motor, you state the voltage, I wanted to know the current but
I suspect a common transistor ought to do.

What is it you are attempting?

 

[Luis]

I hacked this up for you:

http://home.comcast.net/~rcmonsen/ppmotoron/ppmotoron.html

Remember, NEVER CONNECT THE PARALLEL PORT GROUND TO YOUR MOTOR GROUND!
You'll trash your PC with huge inductive spikes. Use optoisolators only.

In addition, I used an OPB680 rather than a normal slot interrupter because
IR can apparently see through some kinds of paper. You might not want that.
The OPB680 has a little plastic door that can get pushed by a piece of paper
without bending the paper. Using something else should work, just check the
current requirements.

http://www.optekinc.com/pdf/OPB680.pdf

If you could post your program on how to control the parallel port (on
alt.binaries.schematics.electronic please) I'd be indebted. Pesky Windows
PCs aren't nearly as friendly to program as a nice MIPS core... no branch
delay slot? You gotta be kidding...

Or you could email it to me at rcmonsen hat comcast dot net.

Regards,
Bob Monsen

Thanks you very much for the schematics, that's what I need!
Do you think I can keep a 100% optical interrupter if I manage to tune
the phototransistor sensivity and/or filter the LED light?

I will send you my source code when I get it working.
Meanwhile I can sugest you the folowing programming resources(high
level languages)
http://www.hytherion.com/beattidp/comput/pport.htm
http://www.logix4u.net/

Regards

 

[Robert Monsen]

[snip]
Thanks you very much for the schematics, that's what I need!
Do you think I can keep a 100% optical interrupter if I manage to tune
the phototransistor sensivity and/or filter the LED light?

I don't know. I'd probably go with the little plastic window, but who knows?
You don't have much to lose by trying it.

Also, look at the schematic again. I just deleted ground connections where
there should not have been any... remember, no connections of any kind
between motor and PC. They were there for simulation purposes.

http://home.comcast.net/~rcmonsen/ppmotoron/ppmotoron.html

I will send you my source code when I get it working.
Meanwhile I can sugest you the folowing programming resources(high
level languages)
http://www.hytherion.com/beattidp/comput/pport.htm
http://www.logix4u.net/

Regards

Thanks, I'll look them over.

Regards,
Bob Monsen