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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.
== Hardware ==
#* Available for about U$1.90 in bulk
# A rechargeable lithium ion cell
#* 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.
#* Energy storage is 1200-2500 mAh
#* There may be challenges getting this shipped to us in bulk - there are tight regulations about the transportation of lithium cells
# PCB
#* 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)
#* Now under considerationdevelopment: Traditional PCB roughly 20x70 mm with clips for cell, ESP module, low-profile tact buttons. Would be nice to include unpopulated (?) header for reprogramming after FSOSS, maybe some other unpopulated pads for LEDs and other things that would make this a fun and useful hacker circuit after the event.
The target cost of the device is <C$5 in the quantities needed for FSOSS (~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.
== Software for FSOSS ==
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.
At present, it is envisioned that the Peapod will:
At the end of FSOSS, attendees will be given the option of:
# returning the Peapod device for re-use by the college and/or safe disposal, or
# 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 about using the Peapod for personal projects will be included in the Peapod information given to each attendee.
== Student Involvement ==
It is proposed that the devices PCB design and software be assembled prepared and flashed tested by Shad Valley volunteer interns in August. The ESP12-F software and the server-side software could be prepared by a volunteer during the summer semester.
== Contacts ==
Project initiator: [[User:Chris Tyler|Chris Tyler]]
