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I have the Brother MFC 490CW printer in my home office that connects to my laptop via WiFi.

There is a sensor in the scanner feeder that senses when a piece of paper has been put in.

I want it to scan automatically and save to file on my laptop as soon as a document is put into the tray.

Is there a way for me to set it up so that the scan happens not on button push in the app to scan, but on document sensor event?

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What does the document sensor do by default? As in, does it open up the scan dialog box on your computer or just "wake" up the scanner?

If it triggers a response on your computer then the easiest thing to do would be to create a macro that clicks the scan button for you. Another more complex option would be to write a small application that listens for the packets from the printer (would probably have to dissect the driver though and use a packet sniffer such as Wireshark for this though).

Otherwise if it just wakes up the scanner then I think you will have to do some form of hardware hack.

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it only wakes up the printer - i have not seen it do anything else – Raj More Jun 27 '11 at 22:43
Ah... yeah that sounds like its going to fall into a hardware project. You would need to tap into the scanner sensor (this would require a little electronics know how), then rig up a system that sends a signal to your computer when it detects a piece of paper (more electronic know how). I would suggest hopping over to , and throwing your question up there. – DesolatorMKX Jun 28 '11 at 16:32

Ideally, you could modify the scanner's driver and figure this out entirely in software.

People who are more comfortable with hardware, like myself, may try something kind of hacky... In the end, it always depends on what your needs are. You could attempt:

  1. Open the scanner casing and discover how the paper sensor works. This may involve use of an oscilloscope.

  2. Interface something to that sensor, or a line the signal you need is pulsed on - I'd use an Arduino for this, for many reasons - mostly cost and they're easily interfaced to a desktop machine.

  3. Have your computer poll (Scheduled Task in Windows, Cron job on Linux) the microcontroller you added in step 2. The microcontroller will respond in kind when it's observed that the signal was sent. The desktop can then go ahead and do whatever else you need done on that end to manage the scanner. It may just be calling the driver to start a scan.

That's sort of a Rubegoldberg / Jeri Ellsworth solution - which is why I kind of love it. I'll reiterate, obviously you'd find a software-only solution. Though my minor experiences with driver hacking were painful and maybe something like this will get your needs met with fewer tears?

Good luck!

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