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{{Chris Tyler Draft}}[[File:Peapod-20160410.jpg|150px|right|thumb|Early Peapod circuit layout, mylar mockup, LiR2050 rechargeable coin cell, and Huzzah development module (carrying the ESP12F module) - April 2016.]]Peapod is the development name for a proposed IoT / User-Interaction device which may be given to attendees at [http://fsoss.ca FSOSS 20162017].This article describes the development of this device from conception through August 2017.[[File:Peapod-1.jpg|150px|right|thumb|Peapod Ver 1.0 device, September 2017. PCB designed by Ethan Childerhose and Samantha Yao.]]

#* LR2050 16850 cell selected (LiR2050 coin cell ruled out, 16850 under considerationdue to capacity)#* This battery was selected because it has a nominal voltage of 3.6v (though a charged cell can output up to 4.2v). The ESP12F has a nominal supply voltage of 3.3v, but 3rd party reports and tests suggest that it can be powered by 32.06-4.2v. Below about 3.0vAt lower voltages, the wifi circuitry does not perform well.

# A flexible printed circuit boardPCB#* Originally considered: A flexible board can be folded over to connect to both sides of the cell, and to create two rows of opposing contacts which can be pressed together by the user to form a connection (i.e., pushbuttons)#* Initial idea is to use a board about 55mm x 75mm (Now under development: Traditional PCB roughly business-card-sized) which will fold in half lengthwise 20x70 mm with a 5mm spacing between the top and bottom layers, yielding a device about 25x25x75mm (1x1x3"), containing the clips for cell, 3 or 4 user pushbuttonsESP module, and the ESP12F module#* A small piece of craft foam will likely need to low-profile tact buttons. Would be inserted into the middle of the device nice to provide stiffness, to separate the two layers, and to act as a spring to keep the user pushbuttons open when they are not depressed#* These circuits could be inkjet printed at the college, or a traditional copper flex circuit production run could be ordered#* The outside include unpopulated ("back"?) of the flex circuit could be printed with the pushbutton labels header for reprogramming after FSOSS, maybe some other unpopulated pads for LEDs and other information, or these could be added in the form of things that would make this a sticker.# A connection scheme to attach the cell fun and ESP12F to the flex useful hacker circuit#* Z-axis electrically conductive adhesive transfer tape (3M type 9703) is one option, though after the ESP12F circuit pads may be too small to permit reliable operation and sufficient current flow (approxevent. 1.5mm2, where the 3M documentation recommends 3.5mm2)#* Alternatives to z-axis tape include wire glue or conductive epoxy, but these limit options for reusing/recycling the device

The total target cost of the device will be in the is < C$3-5 range in the quantities needed for FSOSS (approximately 200~250-250 300 units). Total project cost may be slightly higher depending on what additional devices are required, e.g., development kits, inkjet circuit printer, battery chargers.

The device codename, ''Peapod'', comes from the device size and the original folded-over-circuit design, which are both reminiscent of a pea pod.

The ESP8266 controller used in the ESP12F modules has a large and useful software library available. It can be programmed in Lua or C, with or without an OS (RTOS). There is 4MB of flash memory and 36kB 160 kB of (available) RAM. Software is loaded via a serial interface at 230kbps and further OTA updates to that software are possible.

It To ensure full disclose and opt-in of the attendees:* When the device is proposed that:distributed to each attendee at registration, there will be a brief verbal explanation of the device.* Attendees will be given a privacy statement as part of the Peapod information handout at the registration desk, and the option of opting out of the use of the Peapod.* The devices will be distributed unactivated (battery unattached), and there will be a notice attached to the battery connector.* A short information session will be held at beginning of each day's session. In addition:* Devices will be identified by MAC address only, and no mapping of MAC address to attendee name will be performed.

# keeping the device for their own experimentation. The Lithium cell is rechargeable, and the ESP12F module can be flashed with any software of the user's choice, and those two active components can be removed and used in a project of the user's choice.

Information A link to information about using the Peapod for personal projects will be included in the Peapod information given to each attendee, and we may have a contest at the next FSOSS for the most creative reuse of the Peapod device.

It is proposed that a group of interested students (Club?) be offered the opportunity to become involved with the project to refine the Peapod hardware PCB design and software over the Summer of 2016 be prepared and assemble the devices tested by Shad Valley volunteer interns in September/October 2016August.