Introduction: POV Clock & Message Display W/RTC and PS/2 Keyboard
Below is a short video of it in action
Also to give it something else to do, it defaults to the time when not being used to display messages. I use a Real Time CLock module attached to the Arduino to keep the time current. Without it, the time would need to be set each time the power was turned off.
I used code from various sources and modified as I needed.
The actual build took many turns and went down several dead ends and as such I do not have pictures of the individual steps but I will try to detail as best I can.
Step 1: Supplies I Used
1. piece of wood from basement
2. aluminum pieces from basement
3. misc wires , switches, pcb boards
4. Arduino uno
5. PS/2 connector
6. RTC module from Sparkfun
7. reed switch from Sparkfun
8. 6 wire slip ring from Adafruit
Step 2: The Motor
I used a computer fan which I found at a flea market to be the motor for this project. It is powered by an AC adapter that I had. It outputs 9 volts and 450 mA. This adapter powers both the fan and the Arduino. It is wired thru a switch(see photo). It is secured to the board with screws in each corner.
Step 3: Attachments to the Fan
First I glued a small piece of wood to the fan using an epoxy mix. This would be the base upon which everything else is attached. A second somewhat longer piece of wood is glued to the first. This second piece will be used to attach the aluminum rail which has the 5 LEDs on it.
The five LEDs are inserted into drilled out holes in the aluminum rail and help in place with a small amount of hot glue. The aluminum rail is screwed to the second piece of wood.
Also attached to the rail is a 6 wire slip ring . It is centered over the center of the fan . Then each Led is soldered to one of the six wires. The ground side of the LEDs are all soldered to a common wire ( I used the black one).
The wires that come out of the other side of the slip ring are soldered to lengths of wire and wire tied to the aluminum arm the hangs above the slip ring. The bundle of 6 wires is then routed thru the board to the backside to be attached to the Arduino.
Step 4: The Reed Switch
Also on the front of the board is a Reed switch which is used to trigger the LEDs. It is sitting on a small board which is glued to the board. The wires are routed thru the board to the back to be attached to the arduino.
in order for the switch to operate, I have a small magnet on the end of the screw shown in the photo. Each time it passes the reed switch it will close the reed switch contacts.
Step 5: The Connections on the Back
PS/2 - RTC module - Reed Switch connections
For each of these there are many examples here on Instructables and other sites.
If anyone wants more detail about this particular build, I would be glad to forward what I did.
In the next step I will include my code which is commented freely and should be instructional to some extent.
Step 6: The Code I Used
Step 7: Summary and Comments
This is just a short and not too detailed instructable but I will try to answer questions if they come up.
The 5 LEDs are kind of inadequate for making the letters well defined. Seven or 8 LEDs would be better.
In person the effect of the LEDs is better than the video shows.