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Networked Temperature Monitor

I have two large upright freezers in my garage that I use as beer coolers. Both use an E-bay aquarium temperature controller, to keep my beers at about 50°.

Since I have Rolladen Security Shutters installed on all of the exterior doors and windows of my home, including the door between the house and the garage, I don’t go into the garage often.

One day my wife came from the garage and told me that one of the freezers was making a racket. When I investigated, it turned out that the fan that circulates the cold air was on its way out, and the freezer was struggling to hold temperature. I replaced the fan, and everything was copacetic, but I was concerned about the possibility of another problem that might cause one of the freezers to not hold temperature.

What I needed was something that would allow me to monitor the freezers remotely.

I initially considered one of the wireless indoor/outdoor thermometers that I use in my kitchen, but the wireless signal would not penetrate the metal skin of the freezer.

Then I hit upon using an Arduino microcontroller board to run some One-Wire temperature sensors, and have it serve a web page over my home intranet when interrogated.

I then picked up the following parts:

Freetronics EtherTen: This is a single board that is 100% Ardunio Uno-compatible, and has the equivalent of an Arduino Ethernet Shield baked into a single board. It’s 100% compatible with standard Arduino libraries, and costs about the same or slightly less than the street cost of the two Arduino boards it replaces (unless of course you buy knock-offs off of ebay). It also reduces the overall height of the project, which involves “stacking” the cards.

Freetronics Short Protoshield: This is a prototyping breadboad that fits behind the RJ-45 jack on the Etherten or Ethernet Shield. I used this to hold the connectors and components for the One-Wire system.

DS18B20 Temperature Probes: These probes use a Maxim DS18B20 Digital Thermometer that uses the One-Wire technology that allows multiple devices to share a simple two or three wire microlan. I chose to use the three wire setup, which simply involved placing a 4k7 ohm resistor between DS2 of the Etherten (Uno) and 5V

Adafruit I2C RGB 16×2 LCD Display: This is a slick little kit that allows you to run an LCD display that can change backlight color under software control. It can also be used as a stackable shield, or connected with just 4 wires from the Etherten.

Once I had the boards assembled and stacked, I downloaded the IDE from “Getting Started” webpage. I use OSX, Linux and Windows, so I got the IDE for all three and installed them. I also downloaded the Adafruit RGB LCD Shield Library and the OneWire Library from their respective sites, and loaded them into the appropriate locations in the IDE.

I then wrote some code that will read each probe, and display the result on both the display, and on a simple text-based web page. I used the RGB backlighting to indicate whether or not the temperature was within a specified range. If the temp was too high, the display would turn red:
Too Hot!!

If the temp was too cold it would turn blue:
Too Cold!!

But if everything was correct, then the display would be green:
Just Right!!

You can watch the monitor in action here:

Networked Temperature Monitor

If I ran into a situation where one was too cold, and one was too hot, I opted to display a red screen. Additionally, the red and blue screens both blink on and off as another visual indication of a problem.

I use Powerline Communication Adapters that allow me to use my house wiring for ad hoc ethernet communication. I’ve been using the older 200 MBPS adapter for a while now, and they work great. I can simply put one of the adapters in my garage, connect it to the Etherten, and then interrogate it from any other computer in my home using a web browser:

Web Image

I also use red, blue and green on the web pages to show too hot, too cold, and just right.

I’m planning on doing something similar to monitor Barney, so stay tuned for further developments.

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Charlotte Crosby pulls a series of animated facial expressions in Sydney She complained of a problem with her eyesight earlier in the week. And on Friday Charlotte Crosby was seen pulling a range of facial expressions as she made her way through the Sydney's CBD. The 26-year-old was dressed for comfort in a pair of skinny jeans and a white top, and at one point pulled her long tresses across her face as she made her way through the streets. Scroll down for video Funny girl! Charlotte Crosby has put on an animated display while out in Sydney on Friday pre bonded hairDespite the winter chill, Charlotte completed her casual summery look with black sandals and a grey fringed bag slung over her shoulder. She kept her brunette locks out and straightened with a pair of dark shades on top of her head. The former Geordie Shore starlet previously revealed she was suffering an eyesight problem, earlier in the week. Taking to Instagram on Thursday, Charlotte complained that her eyes were sore after falling asleep in her contact lenses and that she was forced to cancel a trip to the Sydney Opera House. Covering up: The 26-year-old was dressed for comfort in a pair of skinny jeans and a white top, and at one point pulled her long tresses across her face as she made her way through the streets

Ouch: The outing comes after Charlotte was forced to cancel a public appearance because she hurt one of her eyes However she later shared a selfie that showed off the windows to her soul adorned in sparkly gold makeup. The reality TV star told Daily Mail Australia on Thursday that her eye felt painful on a flight from Melbourne, earlier that day and she was worried she had scratched her cornea. remy hair extensionsShe was spotted arriving at Sydney Airport concealing her eyes behind sunglasses. Sore? At one during point during her stroll, the former Geordie Shore starlet looked to be trying to cover her eye Enjoying Australia: Since landing Down Under last weekend Charlotte has been busy enjoying the sights of Sydney and Melbourne She previously tweeted: 'I'm going to the OPERA! How sophisticated! And not just anywhere, (the) SYDNEY OPERA HOUSE'. But Charlotte confirmed she wouldn't be watching the performance of French opera Carmen because she could barely keep her lids open. The Ex On The Beach star also said she was disappointed because she'd picked out 'such a nice dress' for the occasion. Recovered? Taking to Instagram on Thursday, Charlotte complained that her eyes were sore after falling asleep wearing her contact lenses ‘I can’t put makeup on this eye because it’s hurting so much and that would irritate it,' Charlotte said. 'So then what am I meant to do when I’ve got to wear my lovely dress and there will be 5,000 people taking photos? I’m just going to feel awful all night. 'It’s also hurting so I don’t think I could sit and watch the opera for that long because I’m in pain and it’s hard to open my eyes.' ‘I can’t put makeup on this eye because it’s hurting so much and that would irritate it,' Charlotte said of her injured eye Change of plan? Charlotte previously tweeted: 'Tonight I'm going to the OPERA! How sophisticated! And not just anywhere, (the) SYDNEY OPERA HOUSE' Charlotte was also forced to close the curtain in her hotel room because the natural light was hurting it. She added: 'It’s a lot of problems and I don’t feel I can get over any of them in time. I’m really sad about it because I have such a nice dress for it. I hope it will be better in the morning.’ Meanwhile, Charlotte announced her departure from MTV's Geordie Shore earlier this month amid clashes with her ex-boyfriend Gary Beadle. Moving on: Charlotte announced her departure from MTV's Geordie Shore earlier this month amid clashes with her ex-boyfriend Gary 'Gaz' Beadle (right). Pictured during a night out in London last year

She impressed audiences with her gorgeous legs as she flirted with Leonardo DiCaprio in Wolf of Wall Street. And Margot Robbie’s pins were on display as she strolled around New York City in a short black slip dress paired with a long pink Kimono, on Wednesday. The 26-year-old showed why she is tipped to be the next Bond girl, showing off her slender physique in the eye-catching number from Spell & The Gypsy Collective. Scroll down for video perruques cheveux naturelsStepping out: Margot Robbie’s trim pins were on display as she wafted around New York City in a short black slip dress paired with a long pink Kimono on Wednesday The oriental-inspired garment featured broderie anglaise in elaborate flower patterns on the sleeves, shoulders and back, and flowed behind her as she strolled around downtown NYC. Leaving a Tribeca hotel, the Australian actress smiled behind oversized round metallic sunglasses with her blonde locks tied back in a bun. The Hollywood starlet’s complexion was characteristically flawless all over, but years in the Northern Hemisphere appeared to have erased her Australian tan. All smiles: Leaving a Tribeca hotel, the Australian actress smiled behind oversized round metallic sunglasses with her blonde locks tied back in a bun High fashion: The 26-year-old showed why she is tipped to be the next Bond girl, showing off her slender physique in the eye-catching number from Spell & The Gypsy Collective Good taste: The oriental-inspired garment featured broderie anglaise in elaborate flower patterns on the sleeves, shoulders and back, and flowed behind her as she strolled around downtown NYC She enhanced her look with natural-look makeup and subtle pink lipstick and carried a small black leather handbag to run her errands.

Margot had been at a fitting for the upcoming NYC premiere of her new film Suicide Squad on Monday night. Tinseltown is abuzz with rumours that the blonde beauty will appear in the next James Bond film as a Bond girl, following a long line of glamorous actresses. Flawles: The Hollywood starlet’s complexion was characteristically flawless all over, but years in the Northern Hemisphere appeared to have erased her Australian tan Going natural: She enhanced her look with natural-look makeup and subtle pink lipstick and carried a small black leather handbag to run her errands Looking her best: Margot had been at a fitting for the upcoming NYC premiere of her new film Suicide Squad on Monday night Online polls have revealed the 26-year-old stunner is at the strongest odds to fill the role, sitting at 12/1, while Emily Blunt sits at 16/1, according to Paddy Power. Others sitting at promising odds to star as the much-desired female character are American model and actress Emily Ratajkowski, who sits at 22/1, with Brit Emma Watson further down the line at 40/1. The Gold Coast girl found her big break in 2013 opposite Leonardo DiCaprio in Martin Scorsese's The Wolf of Wall Street as the feisty and seductive, Naomi. Plenty to smile about: Tinseltown is abuzz with rumours that the blonde beauty will appear in the next James Bond film as a Bond girl, following a long line of glamorous actresses Adoring fans: Margot caused a stir with passersby as she stepped out in NYC Well made: The beautiful garment had an elaborate rose pattern on its back perruques cheveuxMore recently, she starred alongside Alexander Skarsgård in The Legend Of Tarzan as Jane. As well as the blockbuster, Margot has various other projects in the pipeline, including Suicide Squad, in which she plays Harley Quinn. Other females who have starred as the prestigious Bond girl include talented beauties Halle Berry, Rosamund Pike and Eva Green. Next big thing: Online polls have revealed the 26-year-old stunner is at the strongest odds to fill the Bond role, sitting at 12/1, while Emily Blunt sits at 16/1, according to Paddy Power . In demand actress: As well as the blockbuster, Margot has various other projects in the pipeline, including Suicide Squad, in which she plays Harley Quinn Following in footsteps: Other females who have starred as the prestigious Bond girl include talented beauties Halle Berry, Rosamund Pike and Eva Green Although the buzz around who will land the role of Bond girl is growing, the film is not expected to be released until at least 2018. Producer Barbara Broccoli has two other projects firmly underway and is said to be keen to tempt Daniel Craig into reprising his role as the titular character for the fifth time. Holding her own: Her breakout role was as DiCaprio's feisty wife, Naomi, on Wolf of Wall Street, which her portrayal earned her international acclaim - and showed off her gorgeous legs to the world

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