CC1352R: Simple peripheral not discoverable by iPhone

Which SDK version do you use ?

I am using the SimpleLink™ CC13x2 and CC26x2 SDK, version 3.20.00.68. (Found at this link).

Tested it with 3 Android phones, all can find it. Tested with 2 iPhones, neither finds it.

What app are you using on the phones?

I just test simple_peripheral of SimpleLink™ CC13x2 and CC26x2 SDK, version 3.20.00.68 running on my LAUNCHXL-CC1352R1 and my iphone 7 running TI SimpleLink Starter App can scan and connect to LAUNCHXL-CC1352R1 without problem.

Just the Bluetooth interface implemented by Android and iOS.

You should use TI SimpleLink Starter App to scan and connect to LAUNCHXL-CC1352R1

Thank you. The iPhone now indeed scans the device.

However, we can not connect to it. Neither the Android nor the iPhone devices. I also tried using auto connect, but to no avail. Am I missing something else?
Also, what are the A and B groups in auto connect?

If there is any documentation on the functioning of the Simple Peripheral, besides the demonstrations, that would help.

Do you use TI SimpleLink Starter App to do scan and connect?

Yes. It goes through all 4 retries without success.

What do you mean "It goes through all 4 retries without success."?

The SimpleLink Starter app shows a pop up while connecting to the device, in which it shows Retries: 0 of 4.. Retries 1 of 4.. etc. Eventually it goes through all 4 retries and decides it is unsuccessfull in setting up the connection.

I don't see such issue on my iPhone 7 plus. What iphone model do you use?

Also an iPhone 7. Same issue when using a Galaxy S6 (Android)

Do you use LAUNCHXL-CC1352R1 or your own custom board?

CC1352R1F3 on our custom board.

Thank you for your insight. Indeed, we are actually not using a 32 kHz crystal, but instead we are using the internal RC oscillator. I am currently looking into how to configure everything to support this.