No valid bidirectional (UART) communication between the iMX6 UL-S evk board running the Nordic PC BLE driver and the nRF52 DK running the Nordic connectivity 132 uart software

RE: No valid bidirectional (UART) communication between the iMX6 UL-S evk board running the Nordic PC BLE driver and the nRF52 DK running the Nordic connectivity 132 uart software

Bjørn Inge — Thu, 11 Oct 2018 07:33:29 GMT

Frankthank you for the detailed report. It is of good value to get detailed insight into end products like that. You state valid comments.

Note: I think you willl see that the build scripts and build workflow has improved in the next release of pc-ble-driver, currently consolidate-api branch.

Thanks.

RE: No valid bidirectional (UART) communication between the iMX6 UL-S evk board running the Nordic PC BLE driver and the nRF52 DK running the Nordic connectivity 132 uart software

Frank — Wed, 10 Oct 2018 13:20:13 GMT

Hi Bjørn Inge, all,

Please find my report on the PC BLE driver concept implemented on a custom board running Linux OS.

devzone.nordicsemi.com/.../Nordic_A900_-PC-BLE-driver-concept-implemented-on-a-custom-board_2D00_v40_2D00_20181010_5F00_1445.pdf

Maybe most important the conclusion of my quick succesful proto experience.

Pros:

Very nice concept compared to having to implement yourself the UART driver functionality in plain C to support the HAL transport layer. In other words simplifies/speeds up the implementation process.
Nice C++ implementation.

Contras:

Use of a patch, API version 5 PC BLE driver sources not in sync with the SDK v15 API 5.
Struggling when building the patched project, ble_connectivity_s132v5_hci_pca10040 in SEGGER IDE (flash_placement, debug build fails), this is not the case with the non-patched SDK v15 version.
Strange because normally full support expected for SEGGER.
Not part of the Nordic SDK, it should be see the Pros.
Limited documentation, as far as I know no direct reference on Nordic web page cfr. SDK.

Most surprising to me, is the fact the mismatch of the API v5 applied on the connectivity and PC BLE driver application sources. Despite the mismatch I would rather expect the patch needed on the PC BLE driver application sources regarding the sd function calls.

Also it should be part of the SDK as it is very powerful implementation that simplifies very much the development on the custom board.

Bjorn, thanks for the support the last days, much appreciated.

Best regards,

Frank

RE: No valid bidirectional (UART) communication between the iMX6 UL-S evk board running the Nordic PC BLE driver and the nRF52 DK running the Nordic connectivity 132 uart software

Frank — Tue, 09 Oct 2018 16:20:49 GMT

Hi Bjørn Inge

Great news, it works finally, however it only runs so far with HWFC disabled at both ends so also on the Nordic DK running the connectivity applic!

So I think the extra thing that finally made it work was the patch and especially making the code API v5 compatible at both ends.

Tomorrow, I will look into it if I can get it to work with HWFC enabled, meaning getting the CTS/RTS applicable on the Exceet iMX6 board. I will tryit out with hacking the file descriptor for the serial port.

I'm very pleased however a number of points I want to address that makes it not very confident especially about the patching and the API BLE driver not completely compatible with the SDK v15.

I will give a full report tomorrow of my observations during the last days of development.

However I love very much the concept of the PC BLE driver implementation, this is the way to go for the application board at least if the resources are sufficient enough!

Thanks again for all the support, but I will try to get it to work with the HWFC enabled and report further on the progress I make.

Best regards,

Frank

RE: No valid bidirectional (UART) communication between the iMX6 UL-S evk board running the Nordic PC BLE driver and the nRF52 DK running the Nordic connectivity 132 uart software

Frank — Tue, 09 Oct 2018 14:18:08 GMT

Hi,

Thanks, I will try it out, sounds feasible.

Br,

Frank

RE: No valid bidirectional (UART) communication between the iMX6 UL-S evk board running the Nordic PC BLE driver and the nRF52 DK running the Nordic connectivity 132 uart software

Bjørn Inge — Tue, 09 Oct 2018 13:46:27 GMT

Hi,

in this case Boost does not know whether your system supports HWFC so it simply gives up. If your system supports it you can try to configure it manually. It's getting more complex as you will need to modify the source code of ble-driver (src/common/transport/uart_boost.cpp).

Some pointers:

1. Get the native handle from boost:

fd = serialPort.native_handle(); // fd is of type int

(example: https://stackoverflow.com/questions/30618678/boostasioserial-port-set-rts-dts)

2. Use ioctl to configure the serial port settings

options.c_cflag |= CNEW_RTSCTS; /* Also called CRTSCTS */

(some info here: https://www.cmrr.umn.edu/~strupp/serial.html)

RE: No valid bidirectional (UART) communication between the iMX6 UL-S evk board running the Nordic PC BLE driver and the nRF52 DK running the Nordic connectivity 132 uart software

Frank — Tue, 09 Oct 2018 12:53:43 GMT

Thanks Vidar!

RE: No valid bidirectional (UART) communication between the iMX6 UL-S evk board running the Nordic PC BLE driver and the nRF52 DK running the Nordic connectivity 132 uart software

Frank — Tue, 09 Oct 2018 12:12:59 GMT

Hi Bjørn Inge

No luck with the HWFC setting on Boost UART, it is throwing an exception when enabling the HWFC option.

Experiencing as explained here:

https://stackoverflow.com/questions/28274367/how-to-make-boostasioserial-port-baseflow-control-use-hardware-flow-contro

UART driver issue on Exceet? Would surprise me that HWFC is not possible as CTS/RTS are provided, BOOST issue/compilation...? Any thoughts?

Also no luck with deploying the connectivity applic after applying the patch and changing the Flash placement XML file. So I can build the connectivity applic but it can no longer be deployed via SEGGER, SEGGER throws a failure message when loading up the file despite having a valid connection between PC and board.

Thanks,

Best regards,

Frank

RE: No valid bidirectional (UART) communication between the iMX6 UL-S evk board running the Nordic PC BLE driver and the nRF52 DK running the Nordic connectivity 132 uart software

Bjørn Inge — Tue, 09 Oct 2018 08:24:45 GMT

>>I'm just wondering why is flow control set to none by default in the PC BLE driver applic.

That's a valid question, and the reason it is set to none is that the JLink OB chip on Nordic DevKits have a auto-sensing mechanism for flow control. See the response in this thread https://devzone.nordicsemi.com/f/nordic-q-a/37763/get-no-response-from-connectivity-program-running-on-custom-board-with-pc-ble-driver-hrc-v5-example-host/146070#146070.

Since you do not have a JLink OB chip you need to find the UART settings that works for your device.

RE: No valid bidirectional (UART) communication between the iMX6 UL-S evk board running the Nordic PC BLE driver and the nRF52 DK running the Nordic connectivity 132 uart software

Frank — Tue, 09 Oct 2018 08:10:04 GMT

Hi Bjørn Inge,

Thanks for the extra info, this is good to know, I'm just wondering why is flow control set to none by default in the PC BLE driver applic. As far as I know only baudrate and portname is set.

UartSettings::UartSettings()
	: portName("COM1"),
	baudRate(0),
	flowControl(UartFlowControlNone),
	parity(UartParityNone),
	stopBits(UartStopBitsOne),
	dataBits(UartDataBitsEight)

I will certainly when running the patched Connectivity applic monitor all the UART communication lines.

I will report back.

Thanks,

Best regards,

Frank

RE: No valid bidirectional (UART) communication between the iMX6 UL-S evk board running the Nordic PC BLE driver and the nRF52 DK running the Nordic connectivity 132 uart software

Bjørn Inge — Tue, 09 Oct 2018 07:32:22 GMT

>> Should I work with HWFC enabled in the Connectivity applic? Why is it disabled at the PC BLE driver side?

>> I'm still a bit worried when HWFC is enabled the connectivity applic is no longer responsive after the link control packets are sent.

The HWFC is probably the main culprit at this point. If you disable the HWFC in connectivity you will get some traffic but then at some point the nRF5x chip UART is flooded, leading to loss of data.

>> It seems only failure starts when calling the sd_ble functions

This proves the case for HWFC. You see failure when calling sd_ble function because those packets are longer than the initial control packets. Control packets won't lead to flooded UART, but most sd_ble functions will, meaning operative HWFC is required.

>> I disabled the HWFC as otherwise I don't get any response at all from the Connectivity applic running on the Nordic DK board.

If you have HWFC enabled and don't get any resonse, it probably means that the transmission is blocked by the Exceet IMX6 HWFC lines.

Summary: You need to have operative HWFC

Advice: Hook up the logical analyzer to the UART lines RX/TX/CTS/RTS lines to debug how and why HWFC isn't working.

RE: No valid bidirectional (UART) communication between the iMX6 UL-S evk board running the Nordic PC BLE driver and the nRF52 DK running the Nordic connectivity 132 uart software

Frank — Mon, 08 Oct 2018 20:52:39 GMT

Hi Bjørn Inge

I think I can manage without the wndows batch file have to build automatically the connectivity application that should be compatible with the PC BLE driver applic. Probably the correct SoftDevice hex will also be flashed automatically into the connectivity board after building and running the connectivity applic with SEGGER.

Most important is that the patch is correctly executed on the SDK v15. Except that in my case the serialize pins for UART must remain unchanged, meaning 23, 24,25 and 02 instead of 8, 6, 7, 5.

I'm still a bit worried when HWFC is enabled the connectivity applic is no longer responsive after the link control packets are sent.

But first I will see what the patched SDKv15 solves for me.

Thanks for the support, I will keep you and the Dev Zone informed.

Best regards,

Frank

RE: No valid bidirectional (UART) communication between the iMX6 UL-S evk board running the Nordic PC BLE driver and the nRF52 DK running the Nordic connectivity 132 uart software

Frank — Mon, 08 Oct 2018 12:46:33 GMT

Hi Bjorn Inge,

Thank you for responding to my problem.

I disabled the HWFC as otherwise I don't get any response at all from the Connectivity applic running on the Nordic DK board.

The PC BLE driver runs on the Exceet IMX6 board with flow control set to NONE. I don't get it to work at all when HWFC is enabled on both sides.

So the Connectivity applic responses correctly on the Link Control Packets sent by the PC BLE driver applic (control packets sent in the setupStateMachine: CONTROL_PKT_SYNC, CONTROL_PKT_SYNC_CONFIG,...).

In the H5Transport::processPacket function the syncResponsePacket, syncConfigResponsePacket, etc, are well received/decoded.

It seems only failure starts when calling the sd_ble functions (e.g. sd_ble_cfg_set, sd_ble_gap_adv_data_set, ...) failure occurs (Status 4 , message: Error sending packet to target. Code #3)

I see when adding extra debug output, the BLE driver applic gets a sync packet after "Status 7 connection active is set and the BLE driver is opened" when operating in the ACTIVE state which triggers the RESET state again... and finally the application exists.

Serial port used: /dev/ttymxc2
Baud rate used: 115200
H5Transport open...
start waiting...
start waiting...
open UartBoost... /dev/ttymxc2
opened UART ... /dev/ttymxc2
Info: Successfully opened /dev/ttymxc2. Baud rate: 115200. Flow control: none. Parity: none.

Next state = STATE_RESET
Status: 6, message: Target Reset performed
Next state = STATE_UNINITIALIZED
Got sync response packet for UNINTIALIZED
Next state = STATE_INITIALIZED
Trying to set state in active...
Got sync CONFIG response packet for INITIALIZED
Trying to set state in active...
-----> sets in STATE_ACTIVE
Next state = STATE_ACTIVE
Opened nRF BLE Driver
Status: 7, message: Connection active
Warning: Failed to receive response for command
Status: 4, message: Error sending packet to target. Code #3
sd_ble_cfg_set() failed when attempting to set BLE_GAP_CFG_ROLE_COUNT. Error code: 0x03
Got sync packet for ACTIVE STATE
Going into reset mode...
Next state = STATE_RESET

I hope this extra information helps.

Should I work with HWFC enabled in the Connectivity applic? Why is it disabled at the PC BLE driver side?

Best regards,

Frank

UPDATE: extra info

Internal error (#3) happens as no response message is send back by connectivity applic after sd function was send by PC BLE driver applic.

uint32_t SerializationTransport::send(uint8_t *cmdBuffer, uint32_t cmdLength, uint8_t *rspBuffer, uint32_t *rspLength)
{
// Mutex to avoid multiple threads sending commands at the same time.
std::lock_guard<std::mutex> sendGuard(sendMutex);
rspReceived = false;
responseBuffer = rspBuffer;
responseLength = rspLength;

std::vector<uint8_t> commandBuffer(cmdLength + 1);
commandBuffer[0] = SERIALIZATION_COMMAND;
memcpy(&commandBuffer[1], cmdBuffer, cmdLength * sizeof(uint8_t));

auto errCode = nextTransportLayer->send(commandBuffer);

if (errCode != NRF_SUCCESS) {
return errCode;
}
else if (rspBuffer == nullptr)
{
return NRF_SUCCESS;
}

std::unique_lock<std::mutex> responseGuard(responseMutex);

std::chrono::milliseconds timeout(responseTimeout);
std::chrono::system_clock::time_point wakeupTime = std::chrono::system_clock::now() + timeout;

responseWaitCondition.wait_until(
responseGuard,
wakeupTime,
[&] {
return rspReceived;
}
);

if (!rspReceived)
{
logCallback(SD_RPC_LOG_WARNING, "Failed to receive response for command");
return NRF_ERROR_INTERNAL;
}

return NRF_SUCCESS;

}

RE: No valid bidirectional (UART) communication between the iMX6 UL-S evk board running the Nordic PC BLE driver and the nRF52 DK running the Nordic connectivity 132 uart software

Bjørn Inge — Mon, 08 Oct 2018 12:04:13 GMT

Hi Frank,

you provided a logical analyzer trace to being with. It would be helpful to see another trace now that you have gotten past the initial setup. It might be the HWFC that is not working optimally on your setup, and a trace would give some info on that. Make sure to capture all 4 lines, RX/TX/RTS/CTS.

RE: No valid bidirectional (UART) communication between the iMX6 UL-S evk board running the Nordic BLE driver (from git) and the nRF52 DK (PCA10040) when running the Nordic HR connectivity software

Vidar Berg — Mon, 08 Oct 2018 11:22:05 GMT

Hi Frank,

The pre-compiled connectivity FW binaries are built from a patched version of the connectivity example (\connectivity\ble_connectivity\<board>\ser_sxxx_hci). If you wish to set a different pinout for UART you may apply the provided patch on SDK 15 and re-compile the FW with your pinout, see "compiling the connectivity .hex files" section in installation.md for instructions.

Vidar

RE: No valid bidirectional (UART) communication between the iMX6 UL-S evk board running the Nordic BLE driver (from git) and the nRF52 DK (PCA10040) when running the Nordic HR connectivity software

Frank — Mon, 08 Oct 2018 09:44:23 GMT

Hi Nordic support,

Latest update/progress:

Built and flashed the Connectivity applic, ble_connectivity_s132_hci _pca10040 from the latest SDK v15 [nRF5_SDK_15.2.0_9412b96] into Nordic DK board operating as connectivity board.

The HCI_LINK_CONTROL define is set.

Built the latest PC BLE driver SW and ran it on the Exceet board. I have set the DEFINES NRF_SD_BLE_API=5 NRF_SD_BLE_API_VERSION=5 for compilation.

Debug output:

So I get correct bi-directional communication over the UART (HCI) between both the boards.

The setup state machines passes at startup and response messages from the Connectivity applic running on the Nordic DK are correctly received and handled.

But the process at startup fails to set the command sd_ble_cfg_set, and exits with internal error 0x03.

When for debugging I omit/skip this function at startup, I get an error when trying to set the advertisement data.

What could be the problem? API version mismatch between SDK and PC BLE driver SD API coding?

Thanks in advance,

Frank

RE: No valid bidirectional (UART) communication between the iMX6 UL-S evk board running the Nordic BLE driver (from git) and the nRF52 DK (PCA10040) when running the Nordic HR connectivity software

Frank — Sun, 07 Oct 2018 20:51:28 GMT

Hi all, Nordic Support,

After walking through the SDK's v15 Connectivity applic sources and the PC BLE driver sources things started the clear out for me why the mixing of both applics will not work out of the box.

For the PC BLE driver applic the UART communication is based on the H5 transport layer (encoding/decoding via SLIP protocol including also a CRC of the UART messaging) supporting the 3 wire UART solution for improving reliable UART communication in case of failures (bursts,...).

The SDK's v15 connectivity applic is based on 4 wires UART communication including CTS/RTS next to RX and TX, which means no h5 encoding/decoding at least when using standard UART and NOT UART HCI

Thus messages sent between both boards can't be corretly interpreted as the boards don't speak the same protocol.

So possible solutions to me are:

1. Adapt the connectivity applic to also support the GPIO uart pins P23/24/25/02.

Can Nordic provide the sources of the Connectivity applic that is compatible with the PC BLE driver applic?

2. Adapting myself the Connectivity sources UART HCI from the SDK v15.

3. Implement a uart driver for the custom board cfr. the nrf_drv_uart as proposed in the SDK when implementing the serialize concept for a custom board.

4. Connect physically the standard UART pins from the connectivity board with the custom board UART TX ,RX and ground pins. However is this harmless for both boards when the micro usb is connected to the Nordic Connectivity board.

My preferred solution is number ONE.

Any thoughts, ideas Nordic support?

Thanks in advance,

Frank Vieren

RE: No valid bidirectional (UART) communication between the iMX6 UL-S evk board running the Nordic BLE driver (from git) and the nRF52 DK (PCA10040) when running the Nordic HR connectivity software

Frank — Thu, 04 Oct 2018 21:25:08 GMT

Hi all,

I had a better look at the Nordic BLE connectivity applic supporting UART and it seems a number of UART settings must be adapted to make this work together with PC BLE driver applic running on my Exceet application board.

- parity must be excluded, as the Exceet board implements no parity in the BLE driver SW

- the baudrate must be adapted from 1000000 to 115200

- not quite sure about the HWC but probably it must be kept enabled.

The GPIO pins are set correctly as far as I can see.

I will do the necessary changes and keep the Dev zone informed on my progress.

Best regards,

Frank

RE: No valid bidirectional (UART) communication between the iMX6 UL-S evk board running the Nordic BLE driver (from git) and the nRF52 DK (PCA10040) when running the Nordic HR connectivity software

Frank — Thu, 04 Oct 2018 14:59:47 GMT

Update:

----------

It seems the GPIO pins P 23/24/25 an 02 are not by default enabled to be used as UART when running the connectivity applic from the github project PC BLE driver, correct?

Correctly to say that when running the connectivity HR applic from the SDK these pins become active when doing the serialization setup between 2 Nordic DK's with one acting as connectivity board and the other one as application board. Because this was the first test I did before using the Exceet board as application board.

What to make this work, as the sources from the Git hub project for the connectivity applic are not available?

Thanks,

Best regards,

Frank

RE: No valid bidirectional (UART) communication between the iMX6 UL-S evk board running the Nordic BLE driver (from git) and the nRF52 DK (PCA10040) when running the Nordic HR connectivity software

Frank — Thu, 04 Oct 2018 12:17:34 GMT

Update:

----------

On the Nordic board I no longer measure any voltage between RX and ground or TX and ground. So it seems the UART is blown, so this also means the emulated UART via USB micro is no longer usable?

On the Exceet board voltages between 3.1 and 3.3 are still measured.

No idea how the UART on the Nordic can be destroyed when voltage levels are for both boards between 3.1. and 3.3.

Best regards,

Frank

RE: No valid bidirectional (UART) communication between the iMX6 UL-S evk board running the Nordic BLE driver (from git) and the nRF52 DK (PCA10040) when running the Nordic HR connectivity software

Frank — Thu, 04 Oct 2018 11:35:11 GMT

Update:

-----------

I replaced the Nordic board with another one we had, connected it to a PC running Ubuntu and the PC BLE driver applic worked perfectly. Advertising was done and I could connect it to a smartphone running the Nordic HR application and see the simulated HR data.

My next step was connecting this working Nordic board back to the Exceet board but still without succes.

However when I connect it back to the PC the PC BLE application no longer works and throws the same errors as when using the Exceet board for running the PC BLE application.

So the UART connection made between both boards destroyed something on the Nordic board.

As far as I can see the connection was made correctly, meaning RX (Nordic, PO.28) connected to TX (Exceet) and CTS(Nordic, PO.25) to RTS(Exceet) and vice versa.

How to find out easily what is damaged on the Nordic board? UART checking?

Best regards,

Frank

RE: No valid bidirectional (UART) communication between the iMX6 UL-S evk board running the Nordic BLE driver (from git) and the nRF52 DK (PCA10040) when running the Nordic HR connectivity software

Frank — Thu, 04 Oct 2018 10:43:33 GMT

Hi awneil

As far as I correctly can analyze the reply channel coming from the Nordic board I don't see an answer sent.

Can you confirm that the message sent to the Nordic board is valid? As far as I can see in the code provided in the SDK v15 for the BLE HR connectivity application there is no stripping of the "slip" encoding that is set on any packet (RESET, LINK_CONTROL,...) when sent from the PC BLE driver application.

Also in the documentation of the PC BLE driver there is no reference for using using the SDK application code for the connectivity board. According to the documentation the hex file as provided by the GIT project must be flashed into the connectivity board.

However when I run and debug the SDK HR connectivity HR applic in the SEGGER debugger I trap always a phy error. So no reply is send back.

Honestly I must say the BLE driver code looks awesome to use.

My next tryout is running the BLE driver code on a standard PC with Ubuntu as OS system, this should normally work... otherwise something is wrong with the Nordic board or at least with the SW running on it.

Thanks for the support.

Best regards,

Frank

RE: No valid bidirectional (UART) communication between the iMX6 UL-S evk board running the Nordic BLE driver (from git) and the nRF52 DK (PCA10040) when running the Nordic HR connectivity software

awneil — Thu, 04 Oct 2018 10:29:04 GMT

[quote userid="74361" url="~/f/nordic-q-a/39173/no-valid-bidirectional-uart-communication-between-the-imx6-ul-s-evk-board-running-the-nordic-ble-driver-from-git-and-the-nrf52-dk-pca10040-when-running-the-nordic-hr-connectivity-software"]Any ideas how to proceed further[/quote]

So you've demonstrated that the Exceet is actually sending something.

The obvious next step is to check if the Nordic is receiving it.

Then, if it is receiving, is it sending any reply?