skyBlip Go

A serial of its own, from this page, over Bluetooth.

A new unit neither transmits nor receives until it holds a serial that skyblip.eu signed for it. Its glass says ACTIVATE, names this page, and shows four characters, such as 3F2A, which pick it out in your browser’s list as activate 3F2A skyBlip.

The page asks skyblip.eu, the unit asks you on its glass, and once it holds its serial it starts its radio and takes its name, such as skyBlip Go 00012A. No account, no form: holding the unit is the only proof asked.

Your browser lists the devices in range: pick activate followed by the four characters on the glass.

Device: -
Address: -

The page asks skyblip.eu for a request signed for this unit, and hands it over.
Allow it: the glass says ACTIVATE, SEND THE KEY OF THIS UNIT TO SKYBLIP.EU, press twice.
skyblip.eu gives the unit its serial, and the unit stores it.

Before you start

Chrome or Edge, on a computer or on Android, with an internet connection
The unit switched on and close to you, its glass showing ACTIVATE
Its barometer answering: a unit without one says so on its glass, and cannot be activated
No other app holding the unit’s settings

What happens

One question on the glass, then it flies.

Activate asks the unit for a number it has just drawn, and skyblip.eu signs it. The unit checks that signature against the key of skyblip.eu built into its firmware, so no one else can start an activation, and asks you on its glass. Press twice.

The unit then signs what identifies it with a key of its own, drawn the first time it started and kept in its chip. skyblip.eu checks that signature, assigns the next serial, and signs it for this unit alone. The unit stores it, starts its radio, and the page shows its address: 00, the prefix ADS-L assigned to skyBlip with manufacturer page 49, then the serial in hexadecimal.

The unit checks its serial at every start, and needs this page only once. Activate it again and it keeps the same serial. It keeps its serial too when it moves between a release and a development firmware, which both trust the same key of skyblip.eu.

What skyblip.eu keeps

The unit’s chip identifier, its public key, its serial, the firmware it runs, the date and the internet address the request came from. No name, no email, no account: the serial belongs to the unit, and the key in it is the proof. A unit given away or sold keeps its serial.

When the unit says no

The unit answers	What it means, and what to do
keyless	The unit could not read or make its own key, or name its firmware. Restart it and activate again, and if it happens again, tell us.
no_session	The unit no longer holds the number this activation started from: more than ten minutes passed, or the link dropped. Activate again.
bad_signature	The unit did not recognise what skyblip.eu signed as made for it, now. Activate again, and if it happens twice, tell us which firmware it runs.
small_mtu	The Bluetooth link is too narrow for the unit’s answer. Use a current Chrome or Edge, which ask for wider packets.
in_flight	This unit is already activated, and it has not proven it is on the ground: it is flying, or has had no GPS fix since it was switched on. Take it where it sees the sky, wait for the fix, then activate again.
low_power	The battery is critical, too low to write the serial to memory. Charge it, then activate again.
flash	The unit could not write its serial to its memory. Activate again, and if it happens again, tell us.
expired	Nobody answered the question on the glass within thirty seconds, which counts as a refusal. Activate again, and press twice when the glass asks.
cancelled	The unit said no: one press refuses the question.
claimed	Another app holds this unit’s settings. Disconnect it or close it, then connect again.
unknown_cmd	The firmware on the unit is older than activation, and needs none. Update it from the update page first.
anything else	The unit refused, with a reason this page does not know:

When skyblip.eu says no

The page says	What it means, and what to do
Unknown key	The unit’s firmware trusts a key skyblip.eu does not hold: a build made to trust another key, such as a fork’s. Install a release from the update page, then activate.
Too slow	More than five minutes passed between the request and the presses. Activate again.
Signature refused	skyblip.eu could not verify what the unit signed. Activate again, and if it happens twice, tell us which firmware it runs.
Another key	skyblip.eu knows this unit under another key, so it gave no serial. That follows an erase of the unit’s chip with a debugger. Write to us with the code the page shows after these words: we check with you, then move the serial to the new key. The code:
Key revoked	skyblip.eu revoked the key this unit holds, so it gave no serial. Write to us with the code the page shows after these words. The code:
Enough for today	skyblip.eu has activated as many new units today as it does in a day. Try again tomorrow.
No serial left	Every serial is assigned. Write to us.
Too many requests	Too many requests came from your connection within a minute. Wait a minute, then activate again.
Not understood	skyblip.eu could not read what the page sent. Reload the page and activate again.
No answer	skyblip.eu did not answer: check this device’s internet connection, then activate again.
Failed	skyblip.eu failed to answer:

When the page stops

The page says	What it means, and what to do
Activated	Activated: the unit holds its serial and has started its radio. Its name changes to skyBlip Go followed by its address.
No Web Bluetooth	This browser has no Web Bluetooth. Use Chrome or Edge, on a computer or on Android. Safari, Firefox, and every browser on an iPhone or an iPad lack it.
Not a skyBlip	The device you picked has no skyBlip settings service: it is not a skyBlip.
Link lost	The link dropped. Bring the unit closer, connect again and activate again.
Anything else	Something failed on the way:

Update and set up a skyBlip Go