Hi,

First off thank you for such a great board. I’ve been using the nRF9160DK for development up until now. However I bought the feather because of the RTC and low power features for my requirement.

Anyhow, I received boards today but I cannot program them. Whenever I try and issue
newtmgr -c serial image upload build/zephyr/app_update.bin
I get the following error back
Error: Unknown baud rate 1000000

This is on an AppleMacBookPro Catalina 10.15.7. I installed newtmgr through brew, version 1.7.0.

I have been placing the device in DFU mode, green and blue led solid on.

I’ve tried the following.

  1. newtmgr serial config with no baud rate and nothing happens. It just doesn’t seem to communicate. However, I can run screen on the device and see accelerometer output for the default installed application. So I know the device is functioning and I can receive serial data. Green led on blue led flashing.
  2. Disabling the Apple built in driver bundle for the CP2102 “com.apple.DriverKit-AppleUSBSLCOM”. But that made no difference. I noticed this driver also appears in /dev/tty when the board is connected.
  3. I’ve installed the latest 6.x driver from Silicon Labs. So I have /dev/tty.SLAB_USBtoUART .

Things I have not tried.

  1. Programming on Windows. Maybe this is just and Apple problem.
  2. This forum 🙂

At first I thought it was a driver issue, but maybe now thinking this is a newtmgr problem.

Any suggestions on what the problem could be ?

Regards,
Paul

    Hey Lord-Lucan

    I had to customize newtmgr because the original does not support 1M BAUD. You can download it from here.

      Thanks for the prompt response. Yes this was indeed the issue. I was reluctant to just use downloaded zip file so I installed newtmgr from brew.
      Do you have an MD5 hash of the newtmgr so we can check integrity of the file ?
      Or maybe the changes that were made to the newtmgr sources ?
      Regards,
      Paul

        Lord-Lucan MD5 is 70bf319bd0e983e5927dc14f7c00ba7c

        I’ll have to dig everything up again (it’s been a while since I created this custom version). The gist of it was switching the serial library that newtmgr at the time with one that was more flexible and allowed higher speeds. (Default fastest speed was 115200)

          Terms and Conditions | Privacy Policy