Dexcom G6 and ONE

Basics first

  • Follow general CGM hygiene and setting sensor recommendation here.

General hints for looping with G6 and ONE

  • Recent transmitters are called Firefly. Sensors cannot be restarted without removing the transmitter, which itself cannot be reset, they also do not generate raw data.

  • If you are restarting sensors, ensure you are ready to calibrate and keep an eye on variation.

  • Pre-soaking of the G6/ONE with factory calibration is likely to give variation in results. If you do pre-soak, then to get best results, you will probably need to calibrate the sensor.

Read more in the article published by Tim Street at www.diabettech.com.

If using G6 or ONE with xDrip

  • If not already set up, download xDrip and adjust its settings following the xDrip settings page.

  • Select xDrip in Configuration → BG Source.

  • The Dexcom G6 and ONE transmitters can simultaneously be connected to the Dexcom receiver (or alternatively the t:slim pump) and one app on your phone.

  • When using xDrip as receiver uninstall the Dexcom app first. You cannot connect xDrip and Dexcom app with the transmitter at the same time!

  • If you need Clarity and want to profit from xDrip alarms use the BYODA (only G6) with local broadcast to xDrip.

  • You can also use xDrip as a companion app of the official Dexcom app, but you might experience delays in BG readings. To read the Dexcom app notifications without xDrip, as a trusted data source, use the Notification Reader.

  • xDrip always uses the transmitter’s native algorithm with current transmitters; there is no reason to disable it. Preemptive restarts only function on old transmitters (firmware 1.6.5.25 or earlier), where they are needed to prevent the sensor stopping after 10 days; recent (Firefly) transmitters ignore them. See Restart a sensor before attempting any restart.

  • Everything related to the sensor and transmitter themselves is documented on the xDrip Dexcom page.

If using G6 with Build Your Own Dexcom App

Old app version

Dexcom BYODA is now a very old version of the app and cannot be updated.

  • Build Your Own Dexcom App (BYODA) supports local broadcast to AAPS and/or xDrip

  • This app lets you use your Dexcom G6 with any Android smartphone.

  • Uninstall the original Dexcom app or patched Dexcom app if you used one of those previously (do not stop the currently running sensor)

  • Install the downloaded apk

  • Enter sensor code and transmitter serial no. in patched app.

  • In phone settings go to apps > Dexcom G6 > permissions > additional permissions and press ‘Access Dexcom app’.

  • After a short time BYODA should pick up the transmitter signal.

Settings for AAPS

  • Select BYODA in Configuration → BG Source.

  • If you don’t receive any values select any other data source, then re-select BYODA to trigger the demand for permissions to establish the connection between AAPS and BYODA-broadcast.

Settings for xDrip

  • Select ‘640G/Eversense’ as data source.

  • Command ‘start sensor’ must be performed in xDrip in order to receive values. This will not affect your current sensor controlled by Build Your Own Dexcom App.

If using G6 or ONE with the Notification Reader

The official Dexcom G6 or ONE app stays connected to the transmitter. AAPS reads the glucose value directly from the notification of the Dexcom app, without any other app in between.

Trusted data source

Readings from the Dexcom G6 and ONE apps are a trusted BG data source: SMBs can be allowed all the time.

Compared to BYODA or xDrip, the Notification Reader has limits:

  • No trend arrow and no backfill: readings missed while the phone was off or out of range are lost.

  • Each reading gets the time the notification appeared, not the exact time of the sensor reading.

  • Only values between 40 and 405 mg/dL (2.2 and 22.5 mmol/L) are read. “LOW” and “HIGH” are not read.

Set up the Dexcom app

  • Keep the Dexcom app installed and connected to the transmitter.

  • Make sure the Dexcom app shows the current glucose value in its notification. Its notifications must stay visible: do not silence or hide them.

  • Use the same glucose units (mg/dL or mmol/L) in the Dexcom app as in AAPS. Otherwise AAPS cannot read the value.

Configuration in AAPS

  • Select Notification Reader in Configuration → BG Source and confirm the switch.

    BG Source: Notification Reader selected

  • Back on the main screen, AAPS shows Permissions Required. Next to Notification Access, tap Grant.

    Permissions Required: Notification Access

  • Android opens its notification access list (its name depends on your Android version, for example Notification read, reply & control). Select AAPS, turn on Allow notification access and confirm with Allow.

    Android asks to allow notification access for AAPS

    Android warns that AAPS could read all your notifications. AAPS only reads the notifications of supported CGM apps and ignores all others.

    Notification access allowed for AAPS

  • If Allow notification access is greyed out (Controlled by Restricted Setting), Android blocks it because AAPS was not installed from the Play Store. Open the AAPS app info (long press the AAPS icon > App info), tap the three dots menu at the top right and select Allow restricted settings. Then go back to the notification access screen and allow it.

  • Readings appear in AAPS when the Dexcom app shows a new value.

Warning

If the Dexcom app notification shows more than one glucose number, or none, AAPS skips that notification.

Troubleshooting G6 and ONE

Dexcom G6/ONE specific troubleshooting

  • Scroll down to Troubleshooting here.

General troubleshooting

General Troubleshooting for CGMs can be found here.

New transmitter with running sensor

If you happen to change transmitter during a running sensor session you might try to remove the transmitter without damaging the sensor mount. A video can be found here. If you opt for this solution instead, you must be careful to avoid damaging sensor contacts with the strip.