Assemble the OLED display:
Once you have your inventory of parts in-hand, then assembly can begin. When I created my clock, I started with the OLED display only because I had purchased this item before thinking about a clock! So, the order of assembly is not really important, but you should test the OLED display after assemble and before reprogramming.
Test the display:
The PICAXE 18M2 chip is pre-programmed by Revolution Education, Rev Ed, to include a power-on test message. Simply connect GND (0V) and +5 (V+) to pins marked on header 2 (H2). "In" on H2 is not used in this project. When connected to a well-stabilized +5 volt power supply, the OLED display will display the message:
Line 1: Serial OLED
Assemble the 1-second quartz timer
Carefully follow the instructions provided by Jose Pino. This involves soldering the two diodes and one resistor to the extracted clock board.
Testing the timer:
Because the timer circuit will include an in-line resistor to +5 volts, you can test the circuit by connecting the resistor to +5 and connecting the GND connection to the power supply ground. Then connect the junction of the two diodes (cathodes) to an LED and the other LED connection to ground. The LED should dimly flash each second - reverse the LED pins if the LED does not flash on the first attempt. The voltage at the cathode of the two summing diodes is roughly 4.4 volts and has a duration of about 50Ms (milliseconds) so you may have to try several small LEDs before finding one that you can see when it flashes.
Assemble the IR decoder module:
The exact resistor values used in the IR circuit will be based on the recommendation of the specification sheet for that particular device. My part uses a 10K resistor and a 100 ohm resistor, both 1/4 watt parts but 1/8 watt to 1/2 watt parts will work equally well if you just have them in your parts bin.
Testing the IR decoder:
Consult the manufacturer's specifications for how testing should be accomplished. In my case, I have a digital oscilloscope and I could easily monitor the pulse transitions. Without a scope, you will likely just have to assume the circuit is working and test after connecting to the AXE133Y display board.
Reprogram the AXE133Y with the clock software code:
After download and installation, connect the serial programming cable (USB or RS232) with the pin-plug to the PC and the other end to the AXE133Y programming jack. Power-on the AXE133Y and use the PE Options button to bring up the Options and click on the "Mode" tab and then the "Check Firmware Version..." button. If everything is connected correctly, the PE software will respond with the firmware version of the 18M2 PICAXE chip. You must correct any errors in communications before you can continue.
Download the code from this page to your PC and then open the code in the programming editor by using the "File Open" option. Once the code has been loaded into the programming editor, you can transfer the code to the PICAXE and update the program (sometimes called "burning the [code into the] chip...")
The connections between IR and clock and the AXE133Y module
On the rear of the AXE133Y module is the PICAXE piggyback board that you installed. Labeled on this board are three normally not-used connections: C0, C1, C2. Connection C0 will be used to connect the 1-second pulse from the quartz clock module (the two diode cathodes.) Connection C1 will be used to connect the IR module.
Things to remember:
- The clock display (AXE133Y), the quartz clock module, and the IR module all share the same ground (GND) connection.
- Wires should be kept very short to minimize the effects of AC hum which may be introduced into the IR and Clock lines. An induced electric signal can create havoc with this circuit. You may find that placing a 22K resistor between 0V and C0 on the piggyback board will provide a small load and assist in minimizing interference on the clock line. The best way to avoid interference is to assemble the working circuit into a metal box.
- Setting the clock involves inputting 6 digits, one at a time. The input format is HH:MM:SS and the clock will automatically start with the sixth digit pressed on the remote. If you are attempting to "hack" the time display to a radio or other accurate source, you may need to allow 1/2 to 1 second for the internal software to resync with the correct display after pressing the value for the last second. That is, press the last second input a weebit before the accurate time source indicates that time. Practice makes perfect.
Enjoy you newly built OLED clock with InfraRed, IR, remote settings.
Keep a watch on this link for additional improvements and new software announcements: