The idea behind the eMail Light project is to indicate the presence of emails that are currently on my email server with a flashing LED. I am often not right at my desk and I would like to know if I have email. Or I am near my desk, but my screen saver has kicked in while I’m working on something that doesn’t involve a constant mouse wiggle. By making a little black box with LEDs that can be controlled by USB through a mail monitoring program, I can be alerted to the presence of email on my server.
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Signing UpStep 1: Mail Light Parts
The eMail Light hardware will be made from:
Various tools are appropriate and include (but are not limited to):
- a USBmicro U421 USB interface
- a ULN2803 driver
- a bit of circuit board
- 8 LEDs
- 8 330 ohm resistors
- a small plastic box
- 8 LED mounting rings (optional)
- wire-wrap wire for point-to-point circuit connections
- a small 4-40 machine screw
- an aluminum bar
- solder, solder flux
Various tools are appropriate and include (but are not limited to):
- a screwdriver
- a nutdriver (for the connection to the back of the monitor)
- a soldering iron
- a 4-40 tap (if you tap the bar - optionally use a nut)
- a vise with a brake for bending
- drill and bits for plastic box holes and hole in bar
- flush cutter
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Enabling POP
You can retrieve your Gmail messages with a client or device that supports POP, like Microsoft Outlook or Netscape Mail.
To enable POP in Gmail:
1. Sign in to Gmail.
2. Click Settings at the top of any Gmail page.
3. Click Forwarding and POP/IMAP.
4. Select Enable POP for all mail or Enable POP for mail that arrives from now on.
5. Choose what to do with your messages after they're accessed with your POP client or device.
6. Configure your POP client* and click Save Changes.
The U421 will easily drive a character-based LCD display and that was my first choice. But the LCD can't be read from across the room.
The slim case was found at RadioShack for a couple bucks. Other cases can be used. You can be pretty creative there.
Circuitgizmos accepts PayPal transfers, and accepts credit cards, too. Don't be worried about purchasing through CG.
Feel free to ask any questions about getting the hardware to work for you.
The U451 has the ULN2803 built in PLUS two relays. It is very easy to just add LEDs and a series resistor between +5V and the outputs. The U541 could then give you two relays that switch higher (mains) voltages, six outputs that pull to ground (drive LEDs, more relays) and 8 lines that can be used as input/output.
The circuitgizmos.com site has an email address to ask about Linux examples.
Shipping to Europe is typically about two weeks.
I use a flush-cut tool. I think the Make blog had posted a picture of the things and asked "what do you call this" and there were a lot of different names for it.
After using that tool, I used a knife to trim the bits of remaining plastic.
The board was cut to size by scoring the board and snapping along that score. I commonly use a metal straight edge to guide my cut, and an ordinary "box cutter" as the knife.
Step 1 does have the parts list:
USBmicro U421 USB interface
ULN2803 driver
circuit board
8 LEDs
8 330 ohm resistors
(Obtained from http://www.circuitgizmos.com)
8 LED mounting rings
a small plastic box
wire-wrap wire for point-to-point circuit connections
Not listed was the aluminum bar and screw from a hardware store.
I don't recall where I got the LED mounting rings, but the holes in the box could be drilled out the same size as the LEDs and the rings would not be needed. The box I believe I had picked up at RadioShack - they may or may not still carry them.
Well, Facebook posts. Interesting idea. I personally have a specific account for my Facebook stuff, so even the default free software would work for that. Just set up one of the accounts and associated LEDs for your facebook email account, if that is the case.
Otherwise the default software doesn't do anything too specific. But it is within the capability of programming (in REALbacic in this example, or VB, VC, Java, etc) to look for a specific "from" address to blink the lights.