nRF91 Thingy

[John_Turner]

Hi, 

I have an nRF91 Thingy that arrived last week but it's not operating as expected. I've downloaded the latest version of NRF Connect and I've been following the get started guide.

First I tried to update the cellular modem firmware using MCUboot, I press SW3 while turning on the power and I see a message that "Memory layout is not available in MCUboot mode" but when I try tp update the firmware I receive a message to place the device in MCUboot mode and to try again. The date code on the module looks like 2020.22. Does it come with the bootloader programmed.  

I then tried to register the device on nRF Cloud as an LTE module but either the IEMI or the pin isn't being recognized, the Device ID I'm using is nrf-352656101111642 which matches the IEMI on the module. I'm using the 6 digit pin on the module not the one on the SIM card. 

Questions:

Can the bootloader be programmed using the USB port on the module or is an external programmer required?

The SIM seems to be recognized but are there problems using the nRF9160 modems in Canada. Anecdotally, I located near Vancouver, B.C. in Canada and have an LTE CATM1 module from another vendor operating connecting to the Bell network less then a meter away.

JT

[Carl Richard]

Hi.

Good to hear that it reinstalling nRF Connect solved the MCUBoot issue and apologies for this poor out-of-the-box experience. I will do my best to get you up and running properly.

Did the modem upgrade pass without errors? When upgrading the modem firmware the onboard application is deleted and must be programmed again. However, I'm seeing the same issues myself with the AT_Client as you, so I must look into that. I got it working with the Asset_Tracker, so in the meantime, could you try the following:
1. Update the nRF52840 with the connectivity_bridge again. 
2. Program the thingy91_fw_2020-10-30_5522ca2b/img_fota_dfu_hex/thingy91_ltem_2020-10-30_5522ca2b.hex to the nRF9160. 
3. Observe whether the LED is lighting up and that logs are printed in the LTE Link Monitor. Please report back what you see.

You may have to reboot the device between the operations. 

As mentioned I saw the same issues with the AT_Client when testing here, so hopefully it's only a firmware bug. When using the asset_tracker my Thingy:91 responded to at-commands and logged properly.

Information about the different applications are available in the CONTENTS.txt file. A short description follows:
For the thingy91_nrf9160:
- thingy91_ltem/thing91_nbiot | this is the asset_tracker application, for LTE-M and NB networks respectively. 
- thingy91_at_client | this is the simple at_client application, for communicating directly with the modem through at-commands. There seems to be issues with this one right now.

For the thingy91_nrf52840:
- thingy91_nrf52_connectivity_bridge | this sample enables the nRF9160 to communicate over USB as well as BLE. More information in the documentation.
- thingy91_nrf52_usb_uart_bridge | An earlier version of the connectivity bridge. This is deprecated and should not be used.

Hope the asset_tracker will work for you. I will look into any issues with the at_client.

Best regards,
Carl Richard

[John_Turner]

Hi Carl Richard,

I've upgraded the modem software several times. The first time, and occasionally afterwards, it seemed to stall after the first stage and required re-booting. Most times it proceeds through both stages of programming without issue. Again, I've reprogrammed it several times.

One thing I've tried to do is re-program the unit with the original firmware. The original FW for the modem was 1.1.1 which I found in a 2019 release of the firmware. That version of the firmware only has the USB to UART application. Nothing worked so I reprogrammed it with the latest.

After programming the LED may flicker when power is applied but after that nothing. This is true of any firmware programmed. 

I've been using the LTEM version of the asset tracker application. I resorted to the AT_Client in an effort to see if the Modem was programmed. 

I'll try your suggestions and let you know what happens. 

Is there a way to use the IDE as an alternative to MCUboot without the nRF91 development kit? I also have an older nRF52 development kit but I don't think it's compatible with the nRF9160.

JT

[John_Turner]

Hi Carl Richard,

Some more feedback,

Using a Windows 10 Laptop I was having sporadic success programming the modem firmware so I started using a Win 7 Desktop which worked better. Using the laptop I tried a succession of modem firmware from 1.10 up to 1.23 with no signs of activity (flashing LEDs) using the or connectivity (LTE Monitor).

The procedure I ended up adopting for repeatability was to program the connectivity software first (enabling the MCUboot for the modem), then programming the modem firmware (I tried versions 1.2.2 and 1.2.3), and then programming the LTEM firmware. There was no LED activity at any time. I also tried the NBIOT firmware but again with "no joy".

I'm still open to suggestions but at this point I think it's either a hardware problem or something in firmware that can't be reset using the boot loader. 

JT

[Carl Richard]

Hi, JT!

I understand and I have contacted the developers to see if they have any suggestions. Before concluding with hardware/firmware issues, could I just inquire about your procedure as I haven't managed to reproduce this behavior myself. 

1. It's for the best to use the newest available firmware and applications images when working with the device, so I'd suggest that you stick to the files in thingy91_fw_2020-10-30_5522ca2b.
2. When you program the connectivity firmware did you make sure that it was the nRF52840 that was in bootloader mode? I.e. did you press SW4 (the small, white button next to the nRF9160 SiP, not the big black one) while turning on the device? I just tested myself and no errors will be reported if you program the wrong firmware to the wrong chip. You should only need to do the programming of the connectivity firmware once, as this isn't deleted when the modem is updated. 

The only way to program the Thingy:91 without an external programmer (like the one on the nRF9160DK) is using MCUBoot, either through the nRF Connect Programmer App or on the command line using mcumgr as described in this blog post. The nRF52 DK programmer is unfortunately not compatible with the nRF9160 as you say. 

Please report back if anything is unclear. 

Edit: I can also confirm that there is a bug with the at_client image so that it won't run properly. It is being worked on, but I suggest that you stick to the LTE-M asset tracker firmware for the time being. Sorry for the inconvenience.

Best regards,
Carl Richard

[John_Turner]

Hi Carl Richard,

To confirm my procedure (I verified programming of the connectivity firmware to write this email using the Win 7 computer)

- I start with the nRF91 Thingy powered off. I open nRF Connect (v3.6.1) and start the programmer application (1.4.8). Since the nRF91 Thingy is OFF no devices are indicated in the programmer window.

- I then press SW4 (this is the small white button) and turn on the power. At that time the device is recognized by Windows and an available device is shown in the programmer window (in this case a single COM port)

- I select the HEX file from the DFU directory and then select "Write".Uploading image to device is shown and the progress bar advances. When it completes the message "completed successfully in 50.178 seconds" was displayed. I have foud it necessary to reprogram the connectivity software in order to update the modem.

- on completion I also hear a notification from Windows that a new device has attached and the Programmer shows "THINGY91_e2b4b..." with two com ports as the only available device. 

- in order to upgrade the Modem firmware I would proceed from this point usually by turning off the Thingy, closing the programmer app, disconnecting and reconnecting the USB cable. No device are displayed at this point in the programmer.

- I then press SW3 (the large black button) and turn on power. Windows announces a new device and THINGY91_e24b... is again displayed with two Com ports. Note: using Window 10 only a Zephyr window opens showing the CDC drivers files and only one device appears in the programmer.

- I then select Update Modem and select a *.zip file. I used the mfwnrf9160122.zip file from the 10_30_20 firmware archive. There are four messages displayed, "Step 1/2: ... Uploading image to device", after a short pause "Programming file ..." is displayed followed by "Step 2/2 ... Uploading image to device", and finally "Completed Successfully in 117 seconds". 

 - On completion Windows does not announce a new device but "THINGY91_e2b4b..." is available but I don't beleive it is in MCUBoot mode.

As far as I can tell the programming of both the modem and the connectivity software completes successfully but I see no activity on the LEDs and or communications of any kind. 

Other observations:

- Windows 10 was problematic when programming the modem firmware which is why I shifted to using the Win 7 computer. When the modem software successfully installed using the Windows 10 machine it was taking twice the time as the Win 7 computer.

- nRF Connect was re-installed this week on both machines (3.6.1) and the programmer module is version 1.4.8. 

- I used the CDC divers in the latest nRF52 SDK (17.02) in order to establish communications between nRF Connect and the Thingy91.  

- the older modem firmware installed "easier" on the Window 10 machine, e.g. version 1.1.0. It may have required the older version of USB-UART firmware as well. 

The date codes on the modem (1925E) and the board (2020.22) suggest that the module was build in April of 2020. So my assumption is that the original (operational) firmware would have been from either the 11_29_19 or the 29_04_20 releases which is why I've tried the older firmware. 

If I program the LTEM firmware, besides no LED activity, the THINGY also no longer identifies through USB to Windows, likewise pressing SW3 and cycling power does not result in an MCUboot for the modem. So in order to update the modem I first need to re-program the connectivity firmware which then re-activates the MCUBoot for the modem. 

JT