At the risk of providing too many updates in one week… 😉
Regulatory Testing Results
Regulatory and compliance testing (final EMC scans, EU safety testing, and some special testing required for Grow) went very well overall. We had some minor issues with stability on Thermo, but those were likely related to a manual hardware fix or a firmware issue in our engineering samples rather than a systemic issue. We’re running some regression testing this weekend to see if it was a firmware issue.
On top of the radio system-on-a-chip regulatory and compliance testing (FCC, Industry Canada, ETSI, TELEC), we have now met and passed the following regulatory and compliance standards (on all products unless noted):
– FCC 15 Subpart B (US), Class A (commercial) and the stricter B (residential) for EMC for IT equipment
– ICES003 (Canada) Class A (commercial) and the stricter B (residential) for EMC for IT equipment
– EN 55022 (Europe) IT equipment EMC
– EN 55024 (Europe) IT equipment immunity
– EN 61000-4-2 (Europe) Level 3 (8KV & 4KV) electrostatic discharge to Criteria B (“Temporary degradation which is self-
– EN 61000-4-3 (Europe) radiated immunity
– EN 61000-4-8 (Europe) magnetic immunity
– FCC Part 18 (US) ISM intentional radiator (for Grow’s soil sensor)
– CISPR 11 Part 2/EN 55011:2009 (Canada/Europe) intentional radiator (for Grow’s soil sensor)
– RoHS compliance (actively restricting hazardous substances such as lead, mercury, cadmium etc.)
– WEEE recycling and recovery compliance
*We have to go back early next week and finish ESD testing (EN 61000-4-2) on Sentry, Thermo and Leak. Sentry was a mass production unit that I had to Frankenstein-fix the passive infrared sensor on in a hurry (see previous update), meaning it didn’t then fit properly in its enclosure, which meant it wasn’t suitable for testing just yet. On discussion with the test lab, we may need to add a TVS protection diode to the cables on Thermo and Leak to pass EN 61000-4-2 as the ICs used only have Human Body Model protection.
You may notice that many of these tests were for the European market and wonder “why should I care?” if you’re not in that part of the world. Aside from the fact we need to comply with these standards to sell in Europe (I have to sign a declaration saying we’re complaint with all required standards, which carries criminal liability), the testing benefits all of our customers as you’re assured some additional thought and diligence went into creating the products.
Some of you were very supportive when we mentioned our desire to re-write our entire firmware two months or so ago (some folk even wrote in to say they’d rather we delay shipping and finish the re-write) so that we could support updating the Bluetooth Low Energy (LE) stack. .
For those who don’t recall what we did and why, here’s a refresher:
– We use Nordic Semiconductor’s nRF51 series of Bluetooth LE (Low Energy) system-on-a-chips to power Wimoto’s
– These devices have a software-based Bluetooth LE stack (one of the reasons we like this chipset) rather than burning all of that functionality into silicon or ROM
– We felt strongly that we wanted, if possible, to ship product with a fully upgradeable Bluetooth LE stack (our application was always “over-the-air” upgradeable though) because the Bluetooth LE specification and functionality is evolving at a fast rate
– To do this, we needed to move to a later version of Nordic’s SDK (not a trivial task in itself) and also ship our new firmware with their “SoftDevice 7.x” Bluetooth LE stack
So, we’ve finished this work (two solid months of coding and regression testing) and will be shipping our 1.1 firmware on all devices. What will this do for you?
a) Every software component on our devices (the application, boot loader and Bluetooth LE stack) can now be upgraded over-the-air from an iOS or Android device
b) Our products are now Bluetooth 4.1 compliant (although this doesn’t currently make a lot of difference to the customer experience, it’s a necessary stepping stone to get to the next bit below)
c) Every Wimoto now supports concurrently connecting to a smartphone/tablet/computer AND broadcasting it’s sensor data rather than having to select one or the other. This is important for Mesh, our Internet gateway.
Another reason we did this was to pave the way to allow our products to take advantage of Bluetooth 4.2, which you may have read about in the technology news this past week.
Bluetooth 4.2 brings some very significant and exciting updates to Bluetooth LE:
– 6LoWPAN — this brings “lightweight” IP communication directly to Bluetooth 4.2 LE devices and enables true “Internet-of-Things” connectivity
– Enhanced data transfer — because LE was designed to be very, very aggressive on power consumption, one of the sacrifices was data throughput. This is okay for small amounts of periodic data (heart rate monitors, sensors, etc.) but makes transferring larger amounts of data a little more cumbersome than it could be (think the data logger in your Wimoto, over-the-air software updates)
– Even more power optimization, although improvements are evolutionary rather than revolutionary at this point
We’re still waiting for confirmation from Nordic on exactly what Bluetooth 4.2 features will be supported on the current silicon revisions, but we expect to be offer some sort of meaningful stack upgrade in the near future.
I went and picked up our retail packaging from the printer’s warehouse on Friday. Probably some good advice for other hardware startups looking to crowd-fund: understand the ramifications of scale! This pallet contains 12,000 cartons, probably weighs ~1000lbs/450kg and barely fit in the back of my truck.