Build Instructions

cecio edited this page Sep 30, 2016 · 19 revisions
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Parts List


Power supply block

I'm powering the project using a 9v battery. We need to bring this to 5v for the controller and the RFID reader. The power supply block is based on the L4940V5 voltage regulator and the two capacitors. To build it you can refer to the voltage regulator datasheed or have a look to the following pictures. I cut a matrix board. Put some hot glue on the incoming and outgoing wires soldering point to make them stronger. ps1 the 22uF capacitor is the one nearest to the 9v battery clip. This is the reverse of the board: ps2 then place it in the case as follow (the case is available on Thingverse) ps3

Power Switch

I added on the side of the case a power switch. I used one I had in my lab, you can use whatever you want. NOTE: in the following picture I interrupted the line after the voltage regulator. This is going to drain your battery even when the switch is off. It's better to break the line before, so interrupt the red wire of the 9v battery clip. I already fixed this, but I don't have a clear pitcure :-) ps4

Mount the reader

So, we are almost finished. Now we can mount the RFID reader on the two mounting point and hot glue the copper coil in place. Before placing the board, you have to solder 4 wires from the RFID board. The reader has an USB port, and the connections are replicated on the right side of the board (looking at the picture). The 4 connections are for 5v, GND, RX and TX. You'll have to connect these to the Flora board accordingly. The 5v and ground are the sides connections, the serial are the two in the center:


Mount the controller

Now we have to mount the Flora board, the screen and solder everything. The flora board is mount on a custom stand (available with the case on Thingverse, put a bit of glue to hold it) flora I summarize the connections here:

  • all power lines need to be connected to VBATT
  • connect the GND as you prefer on the available connections point (from RFID, screen and battery)
  • connect the serial from RFID reader to D9 and D10. Don't worry if you invert them, you can reverse in the code
  • SDA and SCL coming from the screen must go to the proper connections on Flora
  • if you use an OLED screen with a RESET line, attach it to D6

Load the code

Now you can open Arduino IDE and load the code from GITHUB