Live access to contents of the microSD inside JeVois

JeVois v1.1

For user convenience, JeVois allows users to access the contents of the microSD card inside the camera live, while the JeVois smart camera is running.

Note

Note that since June 2018 it may be easier to use JeVois-A33: JeVois Inventor graphical user interface. The instructions below do not require JeVois Inventor are are provided in case you do not want to use the Inventor.

Getting started

• Review the instructions in MicroSD card organization and files
• Connect JeVois to a host computer

Starting microSD access from the JeVois command-line interface

When JeVois starts, by default it does not expose its microSD card to the host computer. Users need to request access to the microSD contents explicitly.

Since being able to switch through various vision modules while changing the contents of the microSD poses some potential data consistency issues, for now, we have restricted file access over USB to only work while not streaming video. Likewise, a reboot of the JeVois camera is necessary to allow it to use any new or modified files from th ehost computer.

To instruct JeVois to expose its microSD to the host computer as a virtual USB flash drive:

• Connect to JeVois over the hardware serial port (4-pin connector) or over a serial-over-USB connection. See the following to help you with that:
  • Connecting to JeVois using serial-over-USB: Linux host
  • Connecting to JeVois using serial-over-USB: Windows host
  • Connecting to JeVois using serial-over-USB: Mac host
  • Command-line interface user guide
  • Serial port user guide
  • User tutorial Using the Arduino IDE (Integrated Development Environment) to talk to JeVois
• Send the following command to the JeVois command-line interface:

    usbsd

  You will notice that a new USB flash drive is detected by your host computer.
• Add/modify/remove files. This includes:
  • modify configuration or parameter files in JEVOIS:/config
  • edit a module written in Python, under JEVOIS:/modules
  • add any data, e.g., training images for the ObjectDetect module
  • retrieve any data, e.g., video files recorded by JeVois, under JEVOIS:/data
• When you are done, properly eject the virtual USB drive (drag to trash, click eject button, etc). JeVois will detect this and will automatically restart and then be able to use the new or modified files. You should see the following on the JeVois LED:
  • Blinks off - shutdown complete
  • Solid green - restarting
  • Orange blink - camera sensor detected
  • Solid orange: ready for action

Using shortcut shell command jevois-usbsd

JeVois v1.3

Under Linux, the jevois package provides the command jevois-usbsd in /usr/bin of the host computer, which can be executed directly in any terminal on the host computer (as opposed to being run in the JeVois command-line interface after opening some serial terminal to it). Use it as follows:

jevois-usbsd start

Starts exporting the microSD inside JeVois to the host computer.

jevois-usbsd stop

Properly ejects the previously exported virtual flash drive and reboots JeVois.

Note

jevois-usbsd is a simple shell script. Feel free to look at it. You may be able to create equivalents of that script for Mac and Windows. If so, please contribute them so that others can enjoy your scripts!

On Mac, you can try a simple echo usbsd > /dev/cu.usbmodem* and you should see the virtual USB flash drive JEVOIS appear. Just drag it to trash to eject.

Exporting the JeVois microSD to a Mac host using a simple command in the Mac terminal.