Murata Type 1LD (CYW43438) set Bluetooth LE Tx channel for regulatory testing

[YR]

Hi,

I was redirected here by Murata support.

We use type 1LD on our own custom board. We have a JTAG connection and we use a Segger J-link base to flash it with an app from Cypress WICED SDK.

For regulatory testing we are required to continuously transmit LE packets over the BT middle channel (2440 MHz).

We have tried using hcitool and cybluetool but they require a COM to JTAG, and our J-link does not support that. So the best way for us would be to set it through the embedded app.

We have found the following function in the WICED API:

wiced_bt_ble_set_channel_classification

Which does exactly what we need, but it seems that it is only available for BCM platforms.

Is there an implementation of this for the 1LD?

Or is there any other way to transmit BLE on a specific channel?

Thanks

[DheerajPK_41]

Hi,

For advertisements you can configure it in wiced_bt_cfg_settings_t in wiced_bt_cfg.c. .channel_map = ( BTM_BLE_ADVERT_CHNL_37 | BTM_BLE_ADVERT_CHNL_38 | BTM_BLE_ADVERT_CHNL_39 ),

I hope you need to set the channel for data transmission. Right?

I don't see API support for it. let me check documentation and get back to you.

Thanks,

-Dheeraj

[YR]

Hi Dheeraj,

Thank you for the reply.

Unfortunately we cannot use advertisement for this as we need the channel in the middle of the spectrum (2440 MHz, BT channel 17), and the closest advertising channel is channel 38 at 2426 MHz, which is too far.

So you are correct we need to be able to set the channel for data transmission. We need to be able to transmit on channel 17. Surely there's a way to do it in software?

Thanks.

[YR]

Hi Dheeraj,

Unfortunately we are still in need of that functionality, and are waiting for your assistance.

Thanks.

[DheerajPK_41 · Accepted solution]

Hi,

For this requirement, we suggest you to use the standard SIG HCI command itself. Is there a host MCU connected with 43438 module over UART? If yes, you can try sending the command from the MCU. 

Otherwise may I know how is your device is connected/configured and used.

Please find the attached document. Please check HCI_LE_Transmitter_Test. For more information you can check Bluetooth specification.

Thanks,

-Dheeraj

[YR]

Hi,

We were able to send the HCI command and confirm that it is working using a spectrum analyzer.

Thank you for your help.

YR