Hardware information for Intel Edison-based setups¶
Intel Edison Compute Module - Get it from Amazon, Adafruit, Sparkfun or your nearest provider. Be aware that there are four versions: 1-EDI2.LPON, 2-EDI2.SPON, 3-EDI2.LPOF, and 4-EDI2.SPOF. Option 1 claims lower power consumption, and if so would be better for a portable rig. Option 2 is the more common version, with theoretically higher consumption because of the more power dedicated to wifi. If you purchase a development kit, this is the version you will get. Versions 3 and 4 require an external antenna. To date no one has done any side-by-side testing of power consumption between the LPON and SPON Edison versions, so it is unclear how much difference (if any) the model number would make to power consumption in real-world conditions with an OpenAPS rig.
The different model numbers or variants of the Intel Edison Compute Module do not appear to be documented on Intel’s website or at many of the online retailers. However, the different variants can be seen in the product listings at Mouser and Arrow.
It appears as though the main differences pertain to onboard vs. external antenna and low power vs. high power wireless radio options. The low power radio variant is classified by Intel as “Wearable”. According to some discussion on the Intel message boards (see here and here) the “Wearable” variant limits the wireless radio power to “keep the thermal properties at a lower level”. Some users have noted that their Edison modules get very hot at times. Although the discussions referenced above suggest that using the low power “Wearable” variant may help avoid heat issues, the different Edison models have not been tested side-by-side in an OpenAPS configuration to determine whether or not any one model would use lower power, generate less heat, or have better wireless performance compared to the other models.
Lipo Battery and/or other battery supply¶
Use a LiPo battery because the Explorer Board has battery charger circuitry on board for these batteries. The example setup uses a 2000mah LIPO battery. This battery lasts in the region of ~16+ hours. The connector on this battery is a 2mm 2 pin JST to match the Explorer Board power plug. It’s best to buy from a reputable supplier, because if the internal two cells are mismatched the explorer board cannot charge them seperately and they are prone to catching fire. Make sure that it includes a protection circuit to protect over-discharge. NEVER connect the battery to the Edison base board the wrong way round. There is no manufacturing standard so never assume correct polarity. The connector JP1 on the explorer board has two terminals. The left side is positive, the right side is negative. The side with the JP1 lable is the positive side. Typically a battery’s red wire is the positive wire. Ideally you want a battery that has a 10k ohm thermistor for temperature protection by the Edison too.
You can use any charger with a USB plug, including a wall power charger. The Explorer Board has pass through charging, so this is also how you will charge the LiPo battery.
The following link is to a LiPo battery that is currently most commonly being used with the explorer board rigs. https://www.adafruit.com/products/2011. (If it is out of stock on Adafruit, it can be purchased from various sellers on Amazon here: Adafruit Battery Packs Lithium Ion Battery 3.7v 2000mAh
Explorer Board or another base board¶
You can use just about any base board, including the Intel base board or the Sparkfun base board, both of which are commonly sold with the Edison as a kit. Or, purchase the Explorer Board, which was co-designed by this community. It is going to be the main board supported by the docs moving forward. It also has the benefits of a built-in radio stick.
Radio stick / antenna¶
We recommend the Explorer Board with a built-in radio stick. The antenna on board is a strip of copper underneath the green outer coating. The antenna is labeled A1. It will have its maximum power at 868 MHz. The antenna has a line across it at one point with a label that says “915”. The antenna defaults to the 868 MHz range, which is what WW pumps use. If you have a US pump, mmtune will run and tune to something near 916MHz. Even with the 868 MHz antenna, you should get half a dozen feet or more of range on average. If you want to boost the range of your antenna (optional), then you cut through the outer coating and the copper on that line with an exacto knife. A single clean cut is sufficient, but if the cut doesn’t look clean you could make two cuts and then dig out the circumscribed piece and then reseal the copper with nail polish. With that cut, the antenna will have maximum power near 915 MHz.
If you don’t use the Explorer Board, you can use a number of radio sticks: a TI-USB-Sticks, running subg_rfspy; Wireless Things ERF; Wireless Things Slice of Radio a Slice of Radio; or a Rileylink. For details about setup with these other stick and board options, the best instructions will be found in the mmeowlink wiki for setting up your board and stick. Note you may also need a CC debugger for these. Then, come back to Phase 1 of the docs once you complete that.
You will need two micro USB cables - with a micro connector on one end and a standard (Type A) connector on the other. Most cables will work fine, but some prefer to select lengths. You may already have one for charging a Dexcom receiver, or an Android phone, lying around at home. If you don’t, here’s an example of one that will work: Monoprice Premium USB to Micro USB Charge, Sync Cable - 3ft.
Nuts and Bolts¶
You will likely want to screw your Edison onto the Explorer Board to stabilize the rig. You can order a kit, or use (2) M2 screws and (6) M2 nuts (four used as spacers). Here’s an example of a harware pack with screws and nuts that will work: Sparkfun Intel Edison Hardware Pack
There are a few 3D-printed cases that are being designed, so check back here for more links in the future. A few options that we know will work with an Explorer Board/Edison rig and a standard 2000mah battery: