Blue Charm Beacons

Blue Charm BC068 Detailed Configuration Instructions with screenshots using nRF Connect app:

-Download the free “nRF Connect” app by Nordic Semiconductors from the Google Play Store or from the Apple App Store.

Click the links in the previous sentence to jump directly to the respective app download pages. Alternatively, you can find the app in the Google Play Store or the Apple App Store by searching for “nRF Connect.”

-Turn on the beacon by pressing and releasing the center button (small raised circle on one side of the beacon). You will see the LED light flash blue three times (shining through the plastic housing below the on/off button), indicating that the beacon is now on.

-The beacon is now broadcasting an iBeacon broadcast based on its default configuration. The beacon device name will appear in the nRF Connect app screen whenever it is broadcasting.

-The default configuration settings are as follows:

Broadcast Mode: iBeacon
Device Name: BlueCharm. Can be reconfigured to any name with maximum length of 16 characters.
UUID: 426c7565-4368-6172-6d42-6561636f6e73. Can be reconfigured to any valid UUID (follow this link for a UUID generator webpage)
Broadcast Interval: 1000 milliseconds (i.e. 1 second). Can be reconfigured to any multiple of 50 between 50 and 9000 milliseconds.
Tx Power: 0 dBm. Can be reconfigured to -21, -18, -15, -12, -9, -6, -3, 0, 1, 2, 3, 4, or 5 dBm.
Major: 3838
Minor: 4949
Calibrated RSSI at 1 meter: -52 dBm
Password: (none)

-Before modifying the configuration, it is recommended that you first follow the instructions below in order to understand how to view the current settings via the nRF Connect app.

One final note: You don’t really need to change these default settings at all unless you have more than one of these BC068 beacons. Instead, you can just simply use the default settings of the beacon that are listed above.

Viewing the current configuration settings using the Android version of nRF Connect app

Unfortunately, due to the design of the iPhone system software, the iPhone version and the Android version of the nRF Connect app are somewhat different, with the Android version being much more useful in reading existing configuration settings. Thus, for this section only of the instructions, we will only use the Android version of the app. (Apologies to iPhone users, but this is out of our control. Apple’s policy is to not allow phones to be able to scan and read the configuration settings of “stranger” beacons). 

Note: For CHANGING configuration settings, the Android and iPhone version of the nRF Connect app are equally adept. See further down this page for instructions how to CHANGE the configuration settings. 

-To view the current configuration of the beacon, open the Android version of the nRF Connect app and press SCAN in order to scan for and find your beacon. (If you don’t see the beacon on the main screen of the app, refresh the scan by clicking SCAN in the upper right hand corner of the nRF Connect app screen or by sliding your finger down the screen to refresh).

-Don’t click on CONNECT quite yet, Rather, click on the beacon name, BlueCharm, on the list. This will then open another level of information below the beacon name.

-Using the above screenshot as an example, you can now see the name of the beacon (BlueCharm), the broadcast mode in gray (iBeacon), the measured RSSI at the current moment/position (-48 dBm), the actual broadcast interval (1001 milliseconds; it’s normal to have some slight variation +/- around the configured value), the UUID of the beacon (426c7565-4368-6172-6d42-6561636f6e73), the major (3838), the minor (4949), and the calibrated/fixed RSSI at 1 meter (-52 dBm). Ok, so far so good. Everything matches the default configuration settings. For many users, the beacon can be used without making any changes in these settings, but typically you might want to adjust the name or the major and minor settings of your beacon to differentiate it from other BlueCharm beacons. So, next, we will learn how to adjust these settings.

Changing the configuration settings

-The first step is to decide what settings you would like to change and what you would like to change them to. Then you need to convert these numbers (or words in the case of the beacon name) into hexadecimal. It sounds a bit complicated, but actually it’s fairly simple, plus we have supplied two convenient conversion calculators on this webpage for your use. For illustration purposes, let’s say we have decided to change all the settings as follows (this chart is scrollable on mobile devices):

Setting Type	Limits	Default Value	New Value
Device Name	maximum length of 16 characters	BlueCharm	BlueCharm001
UUID	must be length of 32 characters (0-9; A-F).	426c756543686172 6d426561636f6e73	1A1A1A1A1A1A1A1A 1A1A1A1A1A1A1A1A
Broadcast Interval	any multiple of 50 between 50 and 9000	1000 milliseconds	500 milliseconds
TX Power	-21, -18, -15, -12, -9, -6, -3, 0, 1, 2, 3, 4, or 5 dBm	0 dBm	-3 dBm
Major	unsigned integer values between 0 and 65535	3838	6868
Minor	unsigned integer values between 0 and 65535	4949	7979
Calibrated RSSI at 1 meter	negative signed integer, typically between -20 and -70	-52 dBm	-54 dBm

-The next step is to take our new values above and to convert them to the appropriate hex value inputs that we will then enter into the nRF Connect app.

-First, let’s convert the new name, BlueCharm001, into hex. Since BlueCharm001 is simple text (or ascii in computer-ese), all you need to do is enter BlueCharm001 in the conversion calculator below then click on the CONVERT button:

Convert from ASCII Beacon Name to HEX Enter your preferred beacon name below (maximum 16 characters) then click CONVERT to get the hex value

ASCII Beacon Name

Beacon Name in HEX

-If you have done it correctly, you should now know that the hex equivalent of BlueCharm001 is 426C7565436861726D303031.

-Now, open either the Android version or the iPhone version of the nRF Connect app and press SCAN in order to scan for and find your beacon. (If you don’t see the beacon on the main screen of the app, refresh the scan by clicking SCAN in the upper right hand corner of the nRF Connect app screen or by sliding your finger down the screen to refresh). Tap the CONNECT button next to your beacon name on the screen. After a few seconds, you will be successfully connected with the beacon and will see the following screen:

You are now on the Services page of the app.
From here, Select the Unknown Service UUID 00001803…

You are now on the Characteristics page of the app.
Next, select the upward pointing arrow (since we are going to upload a new name to the beacon) to the right of Unknown Characteristics UUID 00001805…

Next, in the box under Write Value, enter the name command code 11 followed by the new name in hex. Don’t add any spaces or dashes. In our example case, this would mean you would enter 11426C7565436861726D303031 then press SEND.
You will then be returned back to the characteristics page.
On the iPhone version of the app, select Services to go back to the services page, then select Disconnect to disconnect from the beacon, then select Back to go back to the main scanner screen of the app.
On the Android version of the app, click the X next to the beacon name on the upper right part of the screen to completely disconnect that beacon, then select Scanner on the main screen of the Android app to return to the main scanner screen.
You will now see your beacon on the screen but the name does not appear to have changed. Not to worry…click SCAN to refresh the scan, and you will then see the new updated name of the beacon on the screen.

You have now successfully changed the configured name of your beacon.

To change other configuration settings, the process is roughly the same with some small differences as shown in the following chart. Note, you can change as many configuration settings as you want during a single connection. You do not need to disconnect between each Write Value command.

So you don’t overlook it here, we have bolded the command code at the beginning of each Write command below (this chart is scrollable on mobile devices):

Setting Type	Desired New Value	Write Value
Device Name	BlueCharm001	Write 11426C7565436861726D303031
UUID	1A1A1A1A1A1A1A1A 1A1A1A1A1A1A1A1A	Write 121A1A1A1A1A1A1A1A 1A1A1A1A1A1A1A1A
Broadcast Interval	500 milliseconds	Write 160A (see Interval Note below)
TX Power	-3 dBm	Write 1707 (see TX Power Note below)
Major	6868	Write 141AD41F2BCA (see MajorMinorCalibratedRSSI Note below)
Minor	7979
Calibrated RSSI at 1 meter	-54 dBm

** Note for Interval write: Take your desired interval 500ms, and divide by 50 to get 10. 10 is thus the decimal value you want to communicate. But you need to communicate this decimal value in hex terms, so use the “Convert from Decimal to HEX” conversion calculator below to convert decimal value 10 to get hex value 0A.

** Note for TX Power write : After the interval command code 17, select the hex value that corresponds to your desired TX power on the following chart:

dBm	-21	-18	-15	-12	-9	-6	-3	0	1	2	3	4	5
Hex	01	02	03	04	05	06	07	08	09	10	11	12	13

** Note for MajorMinorCalibratedRSSI: The Major, Minor, and Calibrated RSSI configuration values are adjusted with one single combined write command. Use the “Convert from Decimal to HEX” conversion calculator below to convert decimal value of desired Major 6868 to get hex value 1AD4, Minor 7979 to get hex value 1F2B, and Calibrated RSSI -54 to get hex value CA. Start the write with the command code 14 followed by the hex values of major, minor, and RSSI. Be sure not to try to convert the decimal values into hex in one single go. For example, if you try to convert decimal value 68687979-54 all at one time on the conversion calculator, you will get unworkable or incorrect hex values. Also note, many online “decimal to hex” converters do not handle negative signed numbers correctly. The conversion calculator we have on this page can be trusted to handle negative integers.

Here is our simple calculator for converting decimal numbers (a.k.a. “regular numbers”) into hexadecimal numbers (a.k.a. the type of numbers that beacons can handle):

Convert from Decimal to HEX Enter your decimal value below then click CONVERT to get the hex value
Note: Before using the hex value results, remove any leading F characters, e.g. FFFFFFB0 should be entered into nRF Connect as B0. Add a zero in front of 3 digit hex value results, e.g. C51 should be entered into nRF Connect as 0C51. Add a zero in front of 1 digit hex value results, e.g. A should be entered into nRF Connect as 0A. Finally, anything that looks like a zero, is a zero, not a letter O.

Turning off the beacon

-Turn off the beacon by pressing and releasing the center button (small raised circle on one side of the beacon). You will see the LED light flash blue once (shining through the plastic housing below the on/off button), indicating that the beacon is now off.