Start docs on BLE (#1763)

* docs on BLE

* Tip shorted notes

2 files changed, 111 insertions, 0 deletions

diff --git a/Documentation/Bluetooth.md b/Documentation/Bluetooth.md
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+# Bluetooth Low Energy
+
+The Pinecilv2 has hardware support for Bluetooth Low Energy (BLE). This protocol allows reading and writing of parameters to the Pinecil during runtime.
+
+The BLE interface advertises three services, these provide access to live telemetry as well as the ability to read/write settings.
+These are outlined in more detail below.
+
+Pinecil devices advertise themselves on BLE as `Pinecil-XXXXXXX`.
+They also include the UUID `9eae1000-9d0d-48c5-AA55-33e27f9bc533` in the advertisement packet to allow for filtering.
+
+Unless otherwise noted, all data is sent and received as Little-Endian.
+
+As of the time of writing this, notifications are not fully implemented so data will need to be polled. Notification/Indication support will come when there is time to implement it.
+
+## Using the BLE Interface
+
+It is advised to follow the below points when first implementing a BLE integration. Of course once the integration is working feel free to deviate from these. These are just _suggested_ ideas to help kickstart.
+
+1. When filtering for devices, its preferable to filter by the UUID `9eae1000-9d0d-48c5-AA55-33e27f9bc533`, rather than by the device name if possible.
+2. Upon first collection check if the three expected services exist; if they don't the user may have selected an incorrect device.
+3. It's best to read the live bulk endpoint over the live service when its easy to do so (one read vs ~15).
+   1. However if you are just updating one or two line items it may be more efficient to just read these on the live service.
+   2. Feel free to test both and decide.
+4. When reading settings from the device; the association of number <-> setting is fixed, but you may see settings you don't yet know about, make sure you can handle these.
+5. You probably don't want to show unknown setting's to the user though.
+6. Read the device firmware revision and ensure you can decode it. If BLE is revised it may be essential for handling versions cleanly.
+7. It's advisable to keep an eye on the IronOS repository or at least setup the Github watch for release notifications.
+   1. Future releases may revise some BLE aspects or add new settings for example.
+
+## Services
+
+Below is a description of each service. Note that the exact settings are not listed for brevity; it's best to refer to [the uuid lists](https://github.com/Ralim/IronOS/blob/dev/source/Core/BSP/Pinecilv2/ble_characteristics.h) and the [handlers](https://github.com/Ralim/IronOS/blob/dev/source/Core/BSP/Pinecilv2/ble_handlers.cpp) alongside this.
+
+### Live
+
+`UUID: d85ef000-168e-4a71-AA55-33e27f9bc533`
+
+The live services has one characteristic per reading. The readings (in order) are:
+When implementing these; the ones that are not obvious are generally found in the debugging menu. Values are encoded as an unsigned 32 bit number for all results.
+
+1. Live temperature (In C)
+2. Live set point
+3. DC input voltage
+4. Handle temperature (In C)
+5. Power level
+6. Power source
+7. Tip resistance
+8. uptime
+9. Time of last movement
+10. Maximum temperature settable
+11. Raw tip reading
+12. Hall sensor
+13. Operating mode
+14. Estimated wattage
+
+### Settings
+
+`UUID: f6d80000-5a10-4eba-AA55-33e27f9bc533`
+
+The settings service has two special entries; for saving and resetting settings.
+Otherwise all settings are enumerated using UUID's of the format : `f6d7ZZZZ-5a10-4eba-AA55-33e27f9bc533))` where `ZZZZ` is the setting number as matched from [Settings.h](https://github.com/Ralim/IronOS/blob/dev/source/Core/Inc/Settings.h#L16).
+
+All data is read and written in fixed unsigned 16 bit numbers.
+
+#### Settings save
+
+To save the settings write a `0x0001` to `f6d7FFFF-5a10-4eba-AA55-33e27f9bc533`.
+Its advised to not save settings on each change but instead to give the user a save button _or_ save after a timeout. This is just to reduce write cycles on the internal flash.
+
+#### Settings reset
+
+To reset all settings to defaults; write a `0x0001` to  `f6d7FFFE-5a10-4eba-AA55-33e27f9bc533`.
+This will reset settings immediately.
+
+### Bulk
+
+`UUID: 9eae1000-9d0d-48c5-AA55-33e27f9bc533`
+
+The bulk endpoint is where extra data is located with varying read sizes.
+
+#### Live data
+
+The bulk live data endpoint provides all of the data provided in the live endpoint, as one large single-read binary blob. This is designed for applications that are showing large amounts of data as this is more efficient for reading.
+
+#### Accelerometer Name
+
+_Not yet implemented_
+
+#### Build ID
+
+This encodes the current build ID to allow viewing and handling when the BLE format changes.
+
+#### Device Serial Number
+
+This is generally the device CPU serial number. For most devices this can be used as an ID. On PinecilV2 its the MAC address.
+
+#### Device Unique ID
+
+This is only relevant on the PinecilV2. This is a random ID that is burned in at the factory. This is used by the online authenticity checker tool.
diff --git a/Documentation/Troubleshooting.md b/Documentation/Troubleshooting.md
index 7f4c8bb4..1c9ef0eb 100644
--- a/Documentation/Troubleshooting.md
+++ b/Documentation/Troubleshooting.md
@@ -14,6 +14,18 @@ But it is helpful to do some basic diagnostics first just in case the issue is e
 The **VAST** majority of issues are poor soldering or cold solder joints.
 If you can open up your iron, give it a good look at all the connection points, and use another iron to reflow any suspicious ones, this can fix most issues.
 
+## Tip Shorted warning
+
+If you are powering up a device that supports tip resistance detection (TS101 and Pinecilv2 as of present), the firmware checks the readings of the raw tip resistance and sorts these into three "bins". `8 ohm tips`, `6.2 ohm tips` and `tip-shorted`. The tip resistance is used when negotiating USB-PD and in thermal calculations.
+The `tip-shorted` option is selected if your tip is measured to be abnormally small. This could indicate a failed driver mosfet or a failed tip.
+
+When this warning is shown; heating will be disabled to protect from damage. As trying to heat a shorted tip can damage the iron itself.
+
+It is best to take out your tip and manually measure and verify the tip's resistance. It should be 6-8 ohms (depending on tip type). When measuring resistances this small some multimeters can struggle. If you have access to a current limited bench power supply, you can try doing a 4 wire measurement by measuring the voltage drop on the tip while applying a known current. `(R=V/I)`.
+
+If the tip measures correctly you may have a damaged driver mosfet; it would be ideal to open your iron and test the mosfet is operating correctly.
+If after both of these checks everything looks as expected, feel free to open a discussion on IronOS to talk about the issue (Or for Pinecil the community chat can be a much faster response).
+
 ## High tip temp reading when the tip is cool
 
 If you are finding the tip is reading high; the first fields to check in the Debug menu are `RTip` and `CHan`.