Radio Channel 17 connect with Channel 25.

[keunsik]

Dear

Yesterday, i found out this strange symptom.

I monitored long time sensor with Channel 25.

(Ah, OpenThread stack use , SDK 2.5.2 )

By the way, i changed one channel to 17 (it is others RF modem).

By the way, It connected with RF modem using channel 25.

I  use "otLinkSetSupportedChannelMask()" .

Ch 17 : 0x00020000

When i changed channel to  others number, It never connect with channle 25.

Only Channel 17 connect with channel 25.

I try to inspect, But, i can not reason and solution.

I think it is your bug.

one more , SDK Board was nothing symptom.

SDK is nrf52840QIAA

and, my mass production ID is nrf52840QFAA

[Marte Myrvold]

Hi,

To verify, are you only seeing this issue with the device using the incorrect channel on a custom board and not with the nRF52840 DK?

Best regards,
Marte

[keunsik]

Dear,

As i said,

In case my designed Board,  If TX_POWER is under 4 dbm, Sympom is  rare.  Ratio reach tiny.

I can not check on nRF52840dk in detail because i have many works.

I will check tomorrow again. and  i will leave note.

[keunsik]

Dear

I had checked on nRF52840DK  Board.

On SDK Board was nothing symptom.

and, my Board was issued  when connected device is over 2 devices.

It might be a problem about RF matching.

Anyway, i will disable ch25.

[keunsik]

I checked All Channel.

and, I found out all channel is same.

Ch_A+8 = CH_B

Almost 40Mhz Difference is.

For example, Ch11 and Ch19 communicate with each.

Ch12 and Ch20 communicate with each.

....

At first, Device start Leader role.

But, it soon changed child if seding data was detected.

As i said, I can see only my board. not nRF52840DK Board.

is it hardware issue?

[Marte Myrvold]

Hi,

Yes, this seems to be a hardware issue. I will discuss this with one of our hardware experts and get back to you.

Best regards,
Marte