Using NRF52 (NRF52832) as bluetooth module for my psoc 6

RE: Using NRF52 (NRF52832) as bluetooth module for my psoc 6

Hung Bui — Mon, 24 Feb 2025 08:21:37 GMT

Hi Karl-Johan,

Our softdevice controller strictly follows the HCI protocol from Bluetooth SIG so I'm quite surprised that it behave differently to other HCI controller.
It would be easier for me (who doesn't work with raw HCI very often ) if you can translate the commands into readable API commands so I can check why the controller return the error code. Please pay extra attention to the address you use as public address and random address has a different flag bit to indicate if it's random or public (as far as I remember).

[quote user="kjs_eir"]I am facing issue with making my uuids available for the connected device. Indicating that i need to further modify the HCI command sequence. [/quote]

Please give more info on this issue. My suggestion is to try testing/debugging this with a BLE sample (with host and controller running on the same chip). After you make it work you can intercept the internal HCI communication and find the correct HCI sequence/commands.

RE: Using NRF52 (NRF52832) as bluetooth module for my psoc 6

kjs_eir — Thu, 20 Feb 2025 09:18:37 GMT

Hung Bui apperently the hci_uart requires additional configuration from the host in order to start advertising. If i add 0x0105200666371104E5E1 (which sets a connection handler, min and max connection interval) and 0x0109202012110723D1BCEA5F782315DEEF12122315000000000000000000000000000000 (which configured my advertising data, and modify 0x0106200FA000F0000001000000000000000700, so that it uses a random address instead of a public, i can make my device advertise and connectable. Otherwise the "0x010A200101" # HCI LE Enable Advertising is return with a 0x12 error code (invalid HCI command)
u
I found these missing commands by decoding your scope data, thank you very much.

But to me it seems weird that a nordic HCI controller behave so differently then other HCI controller which I work with. Additionaly now that the device is connectable, I am facing issue with making my uuids available for the connected device. Indicating that i need to further modify the HCI command sequence. Any helps would be highly appreciated.

Thanks,

RE: Using NRF52 (NRF52832) as bluetooth module for my psoc 6

Hung Bui — Wed, 08 Jan 2025 09:04:58 GMT

Hi Karl Johan,
You can download Saleae logic software here:
https://www.saleae.com/pages/downloads

It's quite difficult to share the list of command via screenshot. I attached the first few here:

(The above is when we send the advertising data set (Nordic_LBS) as in the screenshot I provided earlier. )

The last one is 010A200101 to start advertising I guess.

RE: Using NRF52 (NRF52832) as bluetooth module for my psoc 6

kjs_eir — Tue, 07 Jan 2025 10:44:26 GMT

Hi Hung Bui

I don't have anything software to open the .sal file, and I cannot read the commands of from the images.
Is it possilbe for you to share a table, image or similar where I can read of the commands?

Since I don't have two nordic boards, I have change med nRF52 DK with nRF52832 to running the peripheral_lbs sample, and connected it to another board running a controller FW. Here i am unable to make the controller start advertising, with the sample. I also see some weird commands being send by the host. A really long stream starting with 0x493A20[...], which my host of cause do not respond to because this is not inline with HCI:

Thanks

RE: Using NRF52 (NRF52832) as bluetooth module for my psoc 6

Hung Bui — Mon, 06 Jan 2025 12:22:55 GMT

Hi Karl,
It's been a while I haven't touched the HCI commands. I think the easiest is to get hold of one extra DK so that you can test with 2 nRF52 DK.

Could you check my last logic trace to see if you can get any thing missing ? maybe you can send the exact same commands and check if it advertise ?

RE: Using NRF52 (NRF52832) as bluetooth module for my psoc 6

kjs_eir — Mon, 06 Jan 2025 11:59:04 GMT

Hung Bui I only have one nRF52 kit, but I can see with my FTDI chip, that flow control works as it should.
My next issue is that i am not able to make the nRF52832 start advertising. I have tried two things

(1) My end setup is the PSOC with the BC832. Here is have modified the overlay file, so it fits with the different pin configuration for the HCI_UART example. And with my scope is can see Uart communication. Decoding this, should make the controller advertise, but I cannot detect it with my BT sniffers

(2) My second setup is the FTDI connect to the UART on the nRF52832, and transmitting the same command sequence to the controller.

Here is the command sequence:

"01030C00", # HCI Reset

"01010C08FFFFFFFFFFFFFFFF", # HCI Set Event Mask

"0106200F0064006400000000000000000000000700", # HCI LE Set Advertising Parameters

"010820070201060654657374", # HCI LE Set Advertising Data ("Test")

"010A200101" # HCI LE Enable Advertising

What am i missing? I can see the response on my scope and everything looks good.

RE: Using NRF52 (NRF52832) as bluetooth module for my psoc 6

Hung Bui — Tue, 17 Dec 2024 15:16:13 GMT

Hi Karl-Johan,
I did a quick test here with the hci-uart and a peripheral_lbs sample and it seems to work fine. You can see in the plot of the 4 pins here:

Zoom in when advertising data is sent:

The CTS (on the host and RTS on the controller) asserted several times during the communication.

Could you try to test on your side ?
Attached is the host application (SDK v2.8.0). I used a nRF52840 DK for the host but it should be similar if you want to test on the nRF52832 DK.(you need to create an overlay file inside boards folder)

devzone.nordicsemi.com/.../7701.peripheral_5F00_lbs.zip

Attached is the Saleae Logic trace:

devzone.nordicsemi.com/.../LBS.sal

RE: Using NRF52 (NRF52832) as bluetooth module for my psoc 6

kjs_eir — Mon, 16 Dec 2024 11:43:47 GMT

Hi Hung Bui

Good to hear, that you are experiencing the same thing. So it seems like flow control is not correct implemented/configured in the sample code?
It have tried to modify the hci_uart_int() in the main.c file to try and "enforce" the flow control.

Here is my updated hci_uart_int()

static int hci_uart_init(void)
{
    LOG_DBG("");

    if (IS_ENABLED(CONFIG_USB_CDC_ACM)) {
        if (usb_enable(NULL)) {
            LOG_ERR("Failed to enable USB");
            return -EINVAL;
        }
    }

    if (!device_is_ready(hci_uart_dev)) {
        LOG_ERR("HCI UART %s is not ready", hci_uart_dev->name);
        return -EINVAL;
    }

    // UART configuration structure
    const struct uart_config uart_cfg = {
        .baudrate = 115200,                 // Set the baud rate
        .data_bits = UART_CFG_DATA_BITS_8,   // 8 data bits
        .parity = UART_CFG_PARITY_NONE,      // No parity
        .stop_bits = UART_CFG_STOP_BITS_1,   // 1 stop bit
        .flow_ctrl = UART_CFG_FLOW_CTRL_RTS_CTS, // Enable RTS/CTS flow control
    };

    // Configure the UART with the flow control settings
    int err = uart_configure(hci_uart_dev, &uart_cfg);
    if (err) {
        LOG_ERR("Failed to configure UART");
        return err;
    }

    uart_irq_rx_disable(hci_uart_dev);
    uart_irq_tx_disable(hci_uart_dev);

    uart_irq_callback_set(hci_uart_dev, bt_uart_isr);

    // Enable UART RX interrupt
    uart_irq_rx_enable(hci_uart_dev);

    return 0;
}

This did not fix the issue, but it caused P0.5 RTS to go high during first transmission, and never to go low again.

Best regards
Karl-Johan

RE: Using NRF52 (NRF52832) as bluetooth module for my psoc 6

Hung Bui — Mon, 16 Dec 2024 11:36:37 GMT

Hi Karl Johan,

I am checking here why the CTS and RTS pins are not used. I tested with some simple sample (echo_bot) and seeing the same issue.

RE: Using NRF52 (NRF52832) as bluetooth module for my psoc 6

kjs_eir — Fri, 13 Dec 2024 12:21:17 GMT

Hi Hung Bui

I will try manually pulling the CTS/RTS pins.

Did you see my first response to your previous reply? I only have one nRF52, but as said. I have tried via the serial connection through the nRF52's interface MCU to nRF52832 where i can write simple uart command, and get a response back. I have tried to mimic HCI command, and it responded fine. But I have yet to figure out the cmd sequence to make the controller(nRF52832) advertising. And here flow control doesn't work either.

RE: Using NRF52 (NRF52832) as bluetooth module for my psoc 6

Hung Bui — Fri, 13 Dec 2024 11:28:15 GMT

Hi Karl,

By having hw-flow-control; in the device tree the hw flow control should be selected, and it's by default the HCI UART (H4) should be.
Have you tried to manually pull the RTS or CTS pin up to see if the communication stop ? Could you try to test with some simple UART sample first ?

Could you try to use Zephyr host to test with the controller ? Meaning using 2 nRF52 to each other ? This way it will be easier for us to reproduce the issue. You can follow the guide here: https://docs.nordicsemi.com/bundle/ncs-2.4.0/page/zephyr/samples/bluetooth/hci_uart/README.html

RE: Using NRF52 (NRF52832) as bluetooth module for my psoc 6

kjs_eir — Fri, 13 Dec 2024 10:10:52 GMT

Hi again @Hung_Bui

I have am running nrf52832 with zephyr's HCI_UART sample, and has connected that to my PSOC.

I am able to read out the following command (from PSOC perspective)
TX: 0x01030C00 (A reset cmd, i assume)
RX: 0x040E0401030C00 (Correct response)

There is a delay between the two above cmd, so i seems like something is taking time to reset...

Next TX is: 0x0119FC060000C0C62D00
RX: 0x040F04010118FX

And then it stops. Nothing happens hereafter.
Flow control is still not working.

Any hints?

RE: Using NRF52 (NRF52832) as bluetooth module for my psoc 6

kjs_eir — Thu, 12 Dec 2024 12:17:39 GMT

Hi Hung Bui

My psoc support HCI interface via UART, so this is the way i am going.

I got the hci_uart example running on the nrf52832 via the nrf52dk eval kit for a start, because when flashin the example onto BC832 directly the uart seems dead.

When talking through a serial port through the interface MCU on nrf52dk to nrf52832. I can send different commands and receive response, I also verified this on my scope. But from my understand should flow-control be enabled? when the board overlay file says:

/* SPDX-License-Identifier: Apache-2.0 */

&uart0 {
compatible = "nordic,nrf-uart";
current-speed = <115200>;
status = "okay";
hw-flow-control;
};

Both CTS and RTS are constantly low, even when transmission is going on. I got the flow control turned on on the switch on the eval board.

I need flow control for my HCI HOST on the PSOC.

Thanks.

RE: Using NRF52 (NRF52832) as bluetooth module for my psoc 6

Hung Bui — Wed, 11 Dec 2024 13:55:43 GMT

Hi Karl-Johan,

Using hci-uart is the right direction if you do have BLE Host stack on the PSOC and if it supports HCI interface on UART.
If you don't have that on the PSOC, you may consider using BLE shell instead.
You can take a look here: Using Bluetooth Shell

The Bluetooth Shell module provide an interface that the peer device can sand UART command to do BLE tasks on the nRF52. It's useful when you want to have both the Host and the Controller stack on the nRF52 instead of the Host on the PSOC and the controller on the nRF52.

RE: Using NRF52 (NRF52832) as bluetooth module for my psoc 6

kjs_eir — Mon, 09 Dec 2024 16:38:11 GMT

Hi Sigurd Hellesvik

Yes, this is what I am looking for. I was hoping to use the example project in zephyr/samples/bluetooth/hci_uart. But I am very new to zephyr, so I am struggling. Could you help me if I am on the right track?

My plan is to (1) create a custom target for the BC832 (because the uart pins are on different pins than the NRF52DK/NRF52832. (2) Compile the HCI_UART project for BC832 board and flash my BC832. (3) From my firmware project running on the PSOC, access the BC832 via HCI.

Does this sound correct?

RE: Using NRF52 (NRF52832) as bluetooth module for my psoc 6

Sigurd Hellesvik — Wed, 05 Jun 2024 14:01:37 GMT

Excluding the previous comment, I do have some information:

[quote user=""]1) is there a specfic .hex which needs to be on my nRF52 when using it as a BT module? if, where can i find this? [/quote]

You need the nRF52 to run as a HCI device. This lets you use it to control BLE from other devices. HCI should be a standard thing. For example, if you configure it as a HCI device, I can connect it to my linux computer and it will be able to use it as a BLE device without me adding any nordic specific configurations (except maybe udev).

To build the HCI code for your nRF52, I would recommend the nRF Connect SDK.

Does this answer your question?

RE: Using NRF52 (NRF52832) as bluetooth module for my psoc 6

Sigurd Hellesvik — Wed, 05 Jun 2024 13:51:42 GMT

Hi,

To develop for the nRF52 series, we recommend the nRF Connect SDK (Which is based on Zephyr RTOS).
See the nRF Connect SDK and nRF5 SDK statement.

We do not officially support Mbed OS. I suggest that you contact mbed OS.

In case any other people find this looking for Mbed OS and wonder why we chose Zephyr RTOS instead, see https://www.embedded.com/will-zephyr-become-the-dominant-rtos/

(I do not actually know anything about the choice as I just work here, but the above link is what I would guess)

Regards,
Sigurd Hellesvik