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MyPic32 Phase II Logs


08/21/2008:
Okay, I made it to Phase II of this challenge, cool, I didnt think my BUM System would even make it this far, apparently this has sparked some interest from the right people!
So I do not want to dissappoint anyone by not going on.... So here we go for Phase II.....

Got all my cool stuff for phase II from the sponsors, thank you Digi-Key, Microchip and all the other partners sponsoring this challenge.

Got my "cool" t-shirt.... (another one to add to my collection of competition t-shirts!! lol)
I have been working on gathering all the components I would need for this phase during phase 1, so now that I have my expansion board for the Pic32 Starter Kit, I can start the hardware prototyping....
I have gotten most of the IC's I am using as free samples from top companies such as Microchip, and Freescale semiconductors.... Most of the components I already had such as the Solid State Relays and PIR sensor....


First prototype PCB milled on my PCB Mill.... this one is for the MPR084Q Capacitive touch sensor controller from Freescale. This IC actually came in a 16Lead QFN package! I'm glad I built my own PCB mill so I could machine small pcb's like these.
Second PCB to be made is for the lower current Solid state relays for the Lighting control. The Heavy duty SSR's are for the higher current draw AC loads such as the exhaust fan.

3rd PCB is the TTL-RS232 Module for the Serial Graphical VFD that I will be using as a user interface for the System.


Now all I have left to Mill is the main Interface PCB that will connect all these individual modules to the Pic32 Expansion Board..... I have had the starter kit for a while and have been tinkering with some code already, so now it is just a matter of hooking these modules up and start playing with some code!!

09/23/2008:

Phase II so far is going good,  I have my prototype circuit boards all finished..... Right now I am just trying to figure out the layout or "look" for the interface in the bathroom, the user interface will consist of the Display and touchpad, no mechanical switches to wear out or get broken, the "touchpads" can actually be separated from each other and be mounted behind a variety of surfaces in the bathroom, such as behind the mirror or something similar to where the user just has to touch the surface above the pad to "actuate" it. Below shows the different modules and components that had to be made and tested.....
The MPR084Q Capacitive Touchpad controller IC Printed Circuit board. This is the controller for the touchpad, it can scan up to 8 touchpads, The Green LED you see in the picture is just there temporarily, there is supposed to be a buzzer connected there so the controller can make key "clicks" when you touch one of the pads, but for now I have an LED in the buzzers place so I can see if it is reading a touch.... much less annoying than little clicks and beeps when your debugging ..... the Red LED is for power indication, mostly added just to see if the board powers up, dont really need it there and I will be removing it before the final install since we dont need anything not too usefull draining power from our "green" device, so every little micro amp of power we can save, the better the efficiency of the product will be in regards to power consumption.
These are the first set of copper "pads" I fabricated out of 18 gauge copper sheet, I used a steel punch we have at work to punch out .875" Diameter round pads. I then soldered wire leads to the back of each plate, I used some  IDE HDD cable wire as the hookup wire.
I then used some masking tape to temporarily mount them under a piece of .125" thick Plexiglass, they worked, but too well, they were too sensitive even under 2 pieces of the plexiglass! so I decided to make the pads a little smaller, you can actually adjust the sensitvity of the sensor through some programming, but I wanted to fine tune the circuit before I do any software tweaking.....
So the new "pads" arent quite round, and these are only .625"x.750", they are still pretty sensitive under .125" thick plexiglass, but not as much as the bigger pads, the very first set I did on a Copper clad board, were too small and the traces I ran for each pad that ran adjacent to another pad could trigger the wrong pad if not touched right on an exact spot.
I ended up making a separate power supply circuit board to power each of my modules off from, since I didnt want to power them off the Pic32 Expansion board itself since there seems to be too much drawing power from them already and I didnt want anything over heating and failing on my prototype.... So I made a small circuit board with 4 volatge regulator connectors on it, they were all milled to accept SOT23A type Voltage regulators but I ended up soldering a TO92 style VR to one output to power something that required almost 200 milliamps. So I ended up with 1-3.3V @ 100 mA, 1-3.3V @ 200 mA, 1- 5v @ 100 mA and 1- 5v @ 250mA. All the components were not installed on the PCB when the pic was taken.
This is my Optically isolated Digital Output Circuit Board (Opto Coupler PCB), this is actually more of a safety omponent for my Pic32 board, this is so I can interface 5 volt Logic to 3.3V logic without worrying about causing any harm to the microcontroller, this will isolate both power sides from each other, and more importantly, the 120Volts AC from the microcontroller!!
This is the Solod State Relay circuit board, this will actually interface the microcontroller to the 120 Volts AC lights and stuff, but through the opto coupler board.... These are rated for lower current draws so I will be using them to turn on the lights, I will be using a differrent SSR for the heavier loads (pictured below)... I will be basically removing the mechanical switches in the bathroom and replacing them with these, I had thought about leaving the switches in place and interconnect them as an ovveride incase something should happen to the pic32 board.... but what could happen right?? ( I can just see Murphy's law 1 through 4 happenning here!!) but for aesthetics, I am going to remove the switches anyway.
These rae the relays I am using for the heavier AC loads such as the exhaust fan.... Not much to say here.....


This is the RS232 Level shifter circuit board for interfacing the VFD to the Pic32.... I ended up adding an onboard 1amp voltage regulator with heatsink to power the VFD right from the same DB9 connector.... I was going to use the MAX233 IC for this board, but all I have on hand is the MAX232 which is for 5v TTL logic, but since I am not sending anything to the Pic32, it works just fine receiving the 3.3volt signals from the MCu and sending them to the display.
And this is the PIR Motion sensor, this will signal the Pic32 when there is motion to automatically turn on the lights in the bathroom when someone walks in, this with other sensors placed around the bathroom to determine when someone is still in the room, but may be sitting still on the toilet, or possibly laying in the tub taking a bath.....
This is all of it wired together and running during testing and initial software testing.... It took me a couple of weeks to get acquainted with this C32 stuff and getting used to using C libraries nad programming in 32 bit instead of what I am used to, 8 Bit Assembly programming (atleast for the Pic Microcontrollers anyway).

This is supposed to be my dining room table, which has been converted to a make shift lab for now, since I am still working on finishing my basement so my work shop is kind of in boxes right now....


Check out my Youtube Video Section to see some of my Video updates for this challenge......


I still have to hook up th RFID reader and do some initial testing on that, but right now, I am working on the Interface panel, to try and give it a "futuristic" look and feel with out it sticking out like a sore thumb in the bathroom....




Stay Tuned! More to come...