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Difference between revisions of "Hack-o-mat"
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== Brain, display and selection == | == Brain, display and selection == | ||
The original hardware was wired to use diodes on a board of switches, where the price was set for each product with five on/off switches, worth 5, 10, 20, 40, and 80 cents. The user would press a button for the product they wanted. Since we don't want to use the buttons that way, we need to use triacs (electronic relays for AC) for each of the 40 product motors. We will use these: | |||
http://www.mouser.com/ds/2/239/MOC302-201763.pdf | |||
their inputs are basically LEDs, and they're totally isolated from the AC output. So we can charlieplex these 40 triacs to just eight GPIO pins from our controller, as long as it has three-state outputs. | |||
We'll be using a $65 Beagle Bone Black for the brain and a $39 android tablet from Fry's electronics with a web app loaded from the Beagle Bone for display and selection. We're planning to have videos of sudoers presenting each item and headphones so people watch, listen and understand what they're bying. We'll probably still hook up the original dispenser buttons, but that's secondary. | We'll be using a $65 Beagle Bone Black for the brain and a $39 android tablet from Fry's electronics with a web app loaded from the Beagle Bone for display and selection. We're planning to have videos of sudoers presenting each item and headphones so people watch, listen and understand what they're bying. We'll probably still hook up the original dispenser buttons, but that's secondary. | ||
One of the reasons for replacing the brain is that our dispenser has a max programmable price per item of $1.85, which conflicts with our desire to sell usb sticks out of the gum dispenser :) It will also make it easy for us to track how much money is spent on each type of item which means we can let other groups, like [https://counterculturelabs.org Counter Culture Labs] sell stuff out of our vending machine and track who should receive how much money without manually counting. | One of the reasons for replacing the brain is that our dispenser has a max programmable price per item of $1.85, which conflicts with our desire to sell usb sticks out of the gum dispenser :) It will also make it easy for us to track how much money is spent on each type of item which means we can let other groups, like [https://counterculturelabs.org Counter Culture Labs] sell stuff out of our vending machine and track who should receive how much money without manually counting. | ||