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The Twilio CLI Microvisor Plugin

Microvisor Public Beta

Microvisor is in a pre-release phase and the information contained in this document is subject to change. Some features referenced below may not be fully available until Microvisor’s General Availability (GA) release.

Current version: 0.3.10

This utility adds Microvisor-oriented functionality to the Twilio CLI tool.



The Microvisor plugin requires Twilio CLI. You can find full instructions for your platform in the Twilio CLI Quickstart guide.

Install the plugin

Run the following command:

twilio plugins:install @twilio/plugin-microvisor

Installing the plugin may result in a number of warnings being output by the installer. We are working to address this.

Update the plugin

After installation, you can keep the plugin up to date by running:

twilio plugins:update

We expect to make a number of improvements to the plugin as Microvisor continues through its pre-release phases and moves toward General Availability. We strongly recommend that you keep your installed plugin updated by running the command shown above regularly.

Plugin 0.3.10 or above is required for Microvisor 0.5.1 or above.


The plugin operates with commands and sub-commands, separated by colons, and entered this way:

twilio microvisor:<COMMAND>:<SUB_COMMAND>

The plugin provides the following commands:

  • apps — Upload application bundles.
  • debug — Enable the decryption of remote debugging signals from a Microvisor-enabled device.
  • deploy — Build and deploy an application to a specified Microvisor-enabled device.
  • info — Get information from a connected Microvisor-enabled device.
  • logs — View messages streamed from a Microvisor-enabled device.
  • wificonfig — Set and check a Microvisor-enabled device’s stored WiFi credentials.


The apps command provides the following sub-commands:

  • bundle — Build an application bundle that can be uploaded. It has two required arguments:
    twilio microvisor:apps:bundle /path/to/bin path/to/bundle/zip

    The latter is the path at which the bundle will be created: the path you will subsequently pass into the create call as shown below.

    If you are using remote debugging, include the debugging public key with the --debug-auth-pubkey switch as follows:

    twilio microvisor:apps:bundle /path/to/bin /path/to/bundle/zip \

    You can generate a suitable private-public key pair with the debug:generate_keypair sub-command.

  • create — Upload an application bundle. It takes as its argument a path to the application bundle to upload:
    twilio microvisor:apps:create /path/to/bundle/zip

    If you specify a path that doesn’t reach a bundle file, or the uploaded file is not a bundle, an error will be thrown.

    Optionally, you may also provide a unique friendly name to help you locate and reference the bundle in future.:
    twilio microvisor:apps:create /path/to/app/bundle <OPTIONAL_UNIQUE_NAME>


The debug command takes a device SID and a path to a remote debugging private key as its arguments. For more information on why this key is required and how it is generated, please see Microvisor Remote Debugging.

twilio microvisor:debug $MV_DEVICE_SID /path/to/private/key/pem

Your call may also include the --listen-port flag, which is used to select the port through which debugging data will flow.

twilio microvisor:debug $MV_DEVICE_SID /path/to/private/key/pem \

The default port is 8001. If you specify an alternative port number, you will need to update your .gdbinit file or run the command

target remote localhost:<PORT_NUMBER>

within gdb.

It also has the following sub-commands:

  • generate_keypair — Generate private and public remote debugging encryption keys. It takes two arguments: paths to where the generated private and public keys shold be stored:
    twilio microvisor:debug:generate_keypair \
      --debug-auth-privkey=/path/to/private/key/pem \

    If you don’t provide either or both key paths, your current working directory will be used.


This command provides a streamlined application build and deploy flow based on the standard Microvisor CMake-based workflow. It has no sub-commands, but takes the path to a CMake project directory (i.e., the directory containing the root CMakeLists.txt file) as a required argument.

The --devicesid switch is mandatory in cases where a deploy will take place, i.e., the call is made without the -b flag. It takes as a value the SID of the device you wish to deploy code to.

The deploy command also provides the following optional flags and switches:

  • -b, --build — Build without deploying.

  • -c, --clean — Clean the build folder first.

  • -d, --deploy — Deploy the most recent build without rebuilding.

  • --genkeys — Generate remote debugging key.

  • --privatekey=<value> — Path to your private key. Default: none.

  • --publickey=<value> — Path to your public key. Default: none.

  • --log — Start logging after a deploy and/or build.

  • --logonly — Start logging immediately without building or deploying.


Build and deploy the app in the working directory:

twilio microvisor:deploy . --devicesid $MV_DEVICE_SID

Build and deploy the app in the working directory, adding remote debugging keys, and initiating logging immediately:

twilio microvisor:deploy . --devicesid $MV_DEVICE_SID --genkeys --log

Build and deploy the app in the working directory, using pre-existingh remote debugging keys:

twilio microvisor:deploy . --devicesid $MV_DEVICE_SID \
  --publickey ~/rdkeys/pukey.pem \
  --privatekey ~/rdkeys/pvkey.pem

Just build the current code:

twilio microvisor:deploy . --build


To use these commands, connect a USB Micro A cable between your computer and, for example, the Nucleo Development Board’s CONTROL port, then press the board’s RESET button. The board’s SYSTEM LED will turn solid blue and your application will halt.

The info command provides the following sub-commands, all of which require you to pass the Unix path to the device file, e.g., /dev/tty.usbmodem14244401 or /dev/ttyACM0.

If you are using Windows, replace /path/to/device in the following sub-commands with the COM port, e.g., COM7. See the wificonfig:ports sub-command, below, for more information.

  • sid — Display the connected device’s SID.
    twilio microvisor:info:sid /dev/cu.usbmodem14101
    Device SID: UVxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx​
  • version — Display the version of Microvisor installed on the connected device.
    twilio microvisor:info:version /dev/cu.usbmodem14101
    Microvisor version: 0.5.1
    Build date: Tue Mar  7 12:39:36 2023​


The logs command provides the following sub-commands:

  • stream — Initiate log streaming. It takes as its argument a device SID — the Microvisor-enabled device from which you wish to receive log messages:
    twilio microvisor:logs:stream $MV_DEVICE_SID

    If you specify a device that isn’t associated with your account, an Unknown device SID error will be thrown.

    Your call may also include the -o flag, which is used to output log messages either in plain text (the default) or in JSON format:

    twilio microvisor:logs:stream $MV_DEVICE_SID -o=json​

    If you select JSON output, you can pipe the output of the command through the JQ utility to present the JSON in a more reader-friendly form:

    twilio microvisor:logs:stream $MV_DEVICE_SID -o=json​ | jq

    The contents of the JSON payload are described below. The plain text output is the value of a message object’s message property.

Only a single log stream can be open to a particular device. If you open a second terminal window and use a new instance of the Twilio CLI to view logs from the same device, the first connection will be closed automatically. You can, however, open multiple streams from multiple devices.

Crash reports

The log output includes the reports issued by Microvisor when an application has crashed. Currently reports are presented in JSON form, and this is the case whether you are outputting to plain text or JSON. For the former, the report JSON is prettified; for the latter, whitespace is removed. For example:


Connection established
Crash Report:
  "basic_registers": {
    "lr": 134219695,
    "pc": 134218520,
    "r0": 536870912,
    "r1": 0,
    "r12": 134219640,
    "r2": 0,
    "r3": 0,
    "xpsr": 1761608192
  "crash_reason": "CPU_FAULT",
  "extended_registers": {
    "r10": 134219640,
    "r11": 134219640,
    "r4": 134219640,
    "r5": 134219640,
    "r6": 134219640,
    "r7": 537395196,
    "r8": 134219640,
    "r9": 134219640,
    "sp": 537395160
  "fast_interrupt_data": null,
  "fault_registers": {
    "bfar": 0,
    "cfsr": 0,
    "fault": 7,
    "hfsr": 0,
    "mmfar": 0,
    "sfar": 0,
    "sfsr": 72,
    "shcsr": 0
  "gtzc_registers": null,
  "special_registers": {
    "control": 0,
    "msp": 537395160,
    "msplim": 0,
    "psp": 0,
    "psplim": 0
Connection dropped


{"category":"connection","connection_id":"c12cfe06-2f7b-11ed-af0e-0a9fcaaa3415","device_timestamp_usecs":null,"message":"Connection established","timestamp":"2022-09-08T13:40:08.731082Z"}


The wificonfig command provides tools to allow you to get, set, and clear WiFi credentials stored on a Microvisor device.

To use these commands, connect a USB Micro A cable between your computer and, for example, the Nucleo Development Board’s CONTROL port, then press the board’s RESET button. The board’s SYSTEM LED will turn solid blue and your application will halt.

The wificonfig command has the following sub-commands, all of which require you to pass the Unix path to the device file, e.g., /dev/tty.usbmodem14244401 or /dev/ttyACM0.

If you are using Windows, replace /path/to/device in the following sub-commands with the COM port, e.g., COM7. See the ports sub-command, below, for more information.

  • get — Get and display the current WiFi credentials.
    twilio microvisor:wificonfig:get /path/to/device​
  • set — Set the device’s WiFi credentials, passed as follows:
    twilio microvisor:wificonfig:set <SSID> <PASSWORD> /path/to/device​
  • clear — Clear any WiFi credentials stored on the device.
    twilio microvisor:wificonfig:clear /path/to/device​

There is an additional sub-command which does not require a device path or any other argument. Indeed it is intended to help you locate your connected Microvisor device by listing the serial devices currently connected to your computer:

  • ports — List currently available device paths:
    $ twilio microvisor:wificonfig:ports
    Available ports on your computer:
    1. /dev/ttyACM0

    $ twilio microvisor:wificonfig:ports
    Available ports on your computer:
    1. /dev/tty.usbmodem14244401

    C:\Users\user>twilio microvisor:wificonfig:ports
    Available ports on your computer:
    1. COM1
    2. COM4

To determine which Windows COM port to use, open Device Manager after you have connected your Microvisor device and check which port listed under Ports (COM and LPT) is labelled USB Serial Port (COMx). This is the COM port you should pass into the get, set, and clear sub-commands.

The list of properties included in the log messages output as JSON is still being defined and is therefore subject to change. You should not build against the following description, which is intended for information purposes only.

You can optionally set the log:stream command to output log messages in their source form, which is JSON. The default output mode emits the value of one of the JSON’s properties, message. The other properties can be accessed by adding -o=json to the command.

Property Name Value(s) Notes
category connection Device-cloud connection status
app_logging Application logging messages
ota_update Microvisor update messages
message Text The exact message depends on the value of category. App logging values are the text issued by the application using mvServerLog(). Connection messages indicate connection status updates
timestamp A Unix timestamp The date and time at which the message was emitted by Twilio


0.3.10 March 20, 2023

  • Provide application deploy functionality based on the standard Microvisor demo code workflow.
  • Provide device SID and Microvisor version information.
  • Updated bundle encryption code to support Microvisor 0.5.1.

0.3.9 February 1, 2023

  • Bug fixes and internal changes.

0.3.8 January 10, 2023

  • JSON output reflects Twilio CLI standard format.
  • Add WiFi credential get, set, and clear functionality.
  • Application logging fixes.
  • Dependency updates.

0.3.7 September 22, 2022

  • Add bundle creation. Note The Python-based bundler tool is now deprecated.

Note Plugin 0.3.6 was an unreleased internal development version.

0.3.5 September 13, 2022

  • Change output switch -o=json|text to match the standard Twilio CLI name. This is a breaking change if you are using the existing switch, --output.

0.3.4 September 12, 2022

  • Add app uploading.
  • Add application crash reports to log output.
  • Add timestamp and message type to text log output.
  • Add remote debugging encyption key generation.

Note Plugins 0.3.1-3 were unreleased internal development versions.

0.3.0 July 29, 2022

  • Support Microvisor application logging system calls.

0.2.0 May 24, 2022

  • Support Microvisor remote debugging with debug command.
  • Use end-to-end encryption for remote debugging sessions. BREAKING CHANGE

0.1.0-0.1.2 April 27, 2022

  • Initial release and follow-up bug-fixes.
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